Caution: this works only when you are asked to calculate cube roots of perfect cubes. Don't brag anywhere and fail if someone asks you cube root of 2198 and you say 12 (using this method)
E_M_E_T Eh, dunno about that. You can be good at your job without knowing maths. This kind of knowledge doesn’t defines someone’s intelligence and ability to do their job well. It’s like knowing countries’ capitals; there isn’t really any merit in learning this kind of stuff by heart. Cant judge someone’s intelligence and abilities based on that.
I have a math degree, worked with numbers my entire career. I’ve never seen this before, it’s very interesting. I love math, in school I would make up my own problems and solve them.....for fun. I’m helping my 10 year old grandson with his math homework and will show this to him. It may give him a leg up on his future classes.
These are quite common vedic tricks in Indian education specially among students preparing for competative exams as we need to be very fast in our calculations. You can look for other tricks too in youtube.
I like math and physics but I realized that I'm really bad at teaching math. Whenever I try to teach my little sister or my friends, they always have trouble understanding. But I am not that bad at teaching (explaining) physics' concepts/theories.
@@anusangeet1869 in higher education you can use calculators for calculations since the problems are big. Lower grades don't need it coz problems are too simple and most probably you won't come across a cube root of 7 digit number there.
I'll give you two interesting things I learned on my own. If you add every odd number starting with 1, no matter where you stop, you will have a perfect square. Also, if you wonder if a number, no matter how large it is, is divisible by 4, 8 16, 32, etc. take the last 2 numbers and if they are divisible by 4, the entire number is divisible by 4; take the last 3 number and, if they are divisible by 8, the entire number is divisible by 8, etc. I'm sure I'm not the first person to figure these things out but I was surprised when I learned them.
Also if the last digits are 0, it will be divisible too, like 500 is divisible by 4 because last 2 digits are zeroes, 5000 is divisible by 8 because last 3 digits are zeroes.
@@user-yx4pb1zk2t I don't know about divisibility criterion. I just found it by accident one day. The square root thing I discovered when I was taking an online IQ test. It gave the following: "16, 25, 36 . . . What is the next number?" I looked and saw 16 + 9 = 25 and 25 + 11 = 36. My response was 49 which was correct but for the wrong reason. It didn't hit me that those numbers were perfect squares. I then followed the rule I came up with and found that it was correct.
she probably did know but was sticking to her rule of never answer math questions on tv. if she started answering easy questions, she’d eventually start being asked harder questions, and when she refused to do them, people would assume she didn’t know how even if she did.
I remember doing this technique when taking a test back in highschool, way before I got into string physics and higher dimensions. I believe it was an exam actually, that consisted of 10 cube root equations to be solved via paper and pencil (show your work). I used this technique mentally, only writing down the table because I had to show work somehow. Couple of minutes I’m the first one done and my teacher is in awe. Feels good
Remember: This only works if the number to be rooted is actually a cube of an integer. Thus, the title should better read "How to calculate the cube root of cubes of integers"!
@FlyingMonkies325 So in your next post detail the steps you would take to find the cube root of 10 to seven places. (-; Btw, if humans and animals couldnt memorize, they couldnt exist.
For sure. After the first example I immediately tried to find the cube root of the earth circumference of 24,896 using this method and it didn't work. I'm not impressed.
+douglas: What he meant when he said that is that the ability to find the cube root of a perfect cube is obviously perfectly useless One can just as easily teach oneself to find the cube root of ANY number, to ANY accuracy desired. What is the cube root of 23.692, rounded correctly to 4 digit accuracy? You can learn to arrive at the solution in a few minutes. 7 digits in perhaps 8 minutes. With pen and paper only.
@@Datisfunny When the last digit is 2,8, 3 or 7, you have to consider the 10's complement of the number i.e. 10 minus the number. So it does correctly arrive at 57
I used to actually know this trick, although i did it with square roots. I had no clue it could work with cube roots too, except it was slightly more complicated. You had to do a wierd subtraction thing from the first digit and i forgot exactly how to do it but this is way easier and more impressiveThanks!
But 125 is easy! 5x5=25 is not hard, and 25x4 is 100 so that helps you remember 25x5 is 125. That's the only one I could have been able to get right because it is so easy.
@@ammaleslie509 all the smaller numbers are easy but that’s not what I was saying. If you don’t know that 39304 for example, is a perfect cube then you can’t apply the trick.
@@creaty2852 That's what I was thinking about... Simply relying on this trick will get urself tricked and propose a seemingly correct answer. I suppose the most secure way is to use Taylor's Expansion
+Baba: Naïve. So what you are saying is that you are "smart" if you know that 5 cubed is 125? Btw, she was not there to be quizzed by little children about basic math. I would have simply said to the brat, tell me the cube root of 300, accurate to 6 places. I can do it, you cannot -- run along now, and take your parents with you.
In my experience, using Newton's method is usually better, especially if you don't know if it's a perfect cube. The trick for cube roots with Newton's method is to make a guess (I usually go with powers of 10), then divide your number by the guess twice, add the guess twice, and divide this by 3. This will give you a much closer overestimate. For 636,056 a good guess would be 100. After you divide twice you get 63.6(056) (you can round to make it easier to do in your head). After you add twice you get 263.6. Divide by 3 to get 87.8. Since this is an overestimate, round down to get 87, which is only one off. (If you repeat again you'll get 86.) The same trick works for square roots and other roots. For square roots, you divide once, add once, and divide by 2. For 4th roots, you divide 3 times, add 3 times, and divide by 4. etc.
Naïve. She was not there to be quizzed about basic math by a child. That is why an adult would not give an answer to such a childish question, in such a setting.. If you don't realize that, you are likely a child.
ronald dump ok "Ronald dump" even if she wasn’t there to be quizzed, it certainly looks worse by not doing the problem then doing it and entertaining he child.
+Heily Kohestani The number 4364 is not a perfect cube, it's a bit more than 16 cubed which is 4,096. The method in the video only works for numbers that are perfect cubes. So you need someone to cube a number and then you can extract the root.
+MindYourDecisions So how to calculate the cube root of a number which is not a perfect cube? And what if the number _is_ a perfect cube, but it has more than 6 digits? I know some people (e.g. Shakuntala Devi) who can perform such calculations mentally, and tell the sequence of decimal digits to whatever precision you ask them for, but they don't reveal how they do it :/
How can I know the perfect cube it or not? - to apply this method... And what practical application, if I can not know a priori, the perfect cube it or not?
DaDanMan Guy I’m not a copy cat I assumed it worked again in the recent update but clearly it’s been patched again that’s all I’m saying. I’m helping people not waste their time lol
Thank you so much Sir I'm in 10th grade. This will definitely help me bcoz we are not allowed to use calculator in exams. Thank you again.... ❤️ Love from India 🇮🇳❤️👍👍👍
For people who say “never if I have to memorize 1-10(rules) I’m out” I can basically throw the statement back to you, how can you memorize a whole fu- 3 minutes long song and can’t memorize a 20 sec rule?
I tried it on the number 1024, assuming I followed your instruction correctly, I cam up with 14. But 14 cubed does not equal 1024. Can you tell me what I did wrong?
+Tamara Enyart The number 1024 is not a perfect cube, it's a bit more than 10 cubed which is 1,000. The method in the video only works for numbers that are perfect cubes. So you need someone to cube a number and then you can extract the root.
A perfect cube is the cube of a whole number. Or that it's cube root is a whole number (without any fractional part). The cube root of 1024 is between 10 and 11, so 1024 is not a perfect cube.
+Tamara Enyart A perfect Cube is like a perfect square. Like 36 is a perfect square because you just need to multiply 6x6 together. So it's any number that is the same number multiplied twice: 2x2, 4x4, 5x5...NxN. Anyways, a perfect cube is like a perfect square, except it's the product of three of the same number: 8 cubed is 2 because 2x2x2=8 and 125 is a perfect cube because 5x5x5=125. SO 2x2x2, 3x3x3, 4x4x4....NxNxN.
a times a times a = perfect cube, if and only if a is a number with no decimal points (integers). For example, 10.08 x 10.08 x 10.08 is not a perfect square, because 10.08 is not an integer.
Psyto x o that's what he meant. I get it, thx. James Reilly uhm.... that's uh.. wat? xD Alprimez So it should be in the proximity of the highest next to? Sounds reasonable.
If I'm being honest this is very useful because they didn't teach us this in pre-cal and it makes so many things so much easier especially if we aren't allowed to use our calculators.
Whenever I stand at the supermarket checkout, I wish to be able to work out the cube root of all the prices. Thank you for this great help in real life.
Crikey, Presh: You astonish me often, but particularly so this time. Who'd'a thunk it? And I have two questions: 1) How do you come up with these ideas/solutions? 2) What software/editing app do you use fo that truly sweet handwriting thing? I have to admit that I'm in love with that penmanship thing.
Thanks. Per question 1, I read about Nicky Morgan and wanted to make a video. I did some research and found this cool trick--if you read the note it's a very old trick, it was actually published in a 1913 newspaper article! Per question 2, I'm planning to make a video on how I make these videos. There is software that I am using, more details to follow.
Hey Presh Talwalkar, thank you so much for taking the time and effort to produce this excellent, easy to understand, video tutorial on how to quickly calculate the cube root of a number that is capable of such without fractions. Keep up the good work!
The cube root of a number that is not a perfect cube would be irrational. Infinite decimal places, not a fraction. But I'm just knit picking. I also enjoyed the tutorial.
what if the number goes past a million, like 1,016,139 we keep 9 9 then we ignore last 3 digits getting 1,016 it goes past a thousand, so what do we do there
isnt 185 closer to the cube of 6 than to the cube of 5 in the example with the cube root of 185193? because 185 is 31 less than 216 (6^3) and 60 more than 125(5^3)
Akira Nishiki The algorithm is to round down when you're between two numbers. (In the video I wrote closest cube without "going over" by which I meant to round down).
haha wow, i failed there :D no need to be rude though. also it would be weird, if educational videos were for the intelligent elite only. asking questions can´t ever be wrong, especially if you were dumb. Being offensive to the less intelligent won´t make them smarter, spreads hatred and is just dumb. You don´t need to hurt others with your words just to feel better. Just give it a try, everyone makes mistakes :) I´ll edt the post, also the main question and problem i had would have stayed the same, but was already answered ;)
that is awesome, now i have just to learn by hard and it is nice to recover that channel. it was recommended to me in summer 2020. I forgot the name of this channel but i found it again and it is awesome
They don't, but you are purposely starting with a number that doesn't have a nice clean cube root. This trick assumes that a person takes a number between 0 - 100 and cubes it, and then you cube root it in your head. To pick an arbitrary random large number would be cheating at this game.
Thank you. This is a wonderful video to find cube root of perfect cubes. Most important part is... to remember the numbers. So 1:28 is the main point of this whole video
I think it helps for large numbers. An easy way to remember is by drawing a picture by connecting the numbers on the phone dial. It forms a mirror image of itself and it's really simple to memorize it thereafter.
@FlyingMonkies325 Sir, the point here is to find the cuberoot of a number, not the cube of it. You cannot use the method you suggested to arrive at the cuberrot of a number. Sir, here is a number: 479,321. Now, in the next post detail how you would find the cube root of it using your method, or the guy in the vids method. The proof is in the doing, not the yadda, yadda, yadda
I suspect she didn't want to answer because if she did people would ask her increasingly more difficult math questions. That being said some people really are that bad. An ex boss of mine spent 5 minutes looking for a calculator to work out 5+8. Another asked what I was doing when I used long addition on a piece of paper, I actually had to explain the concept.
Trevor Mccord Never understood how you'd work out 25 goes into 125 5 times without having memorised it, to me it's just trial and error until I figure it out, no real method.
@@meg_8518 I took a test back in 5th grade to see if I could skip to 7th. I ended up going through the entirety of high school during my middle school years and got to college at 15. After graduating at the top of my class at M.I.T and studying theoretical quantum physics on my spare time, I am sad to say that I can't figure out who asked
@@theweirdwolf1877 I guess different countries’ math teaching speed is different. I’m in Canada and I moved there from Hong Kong, and Hong Kong math is taught 2 years faster than Canada math, so I’ve already learned most stuff in grade 8 and I was supposed to learn cube roots in Hong Kong grade 8
You can learn to find the cube root of ANY number if you like. The material in the vid will not help in any way. Here is a number: 65893.28. I just evolved the cube root of it rounded correctly to 7 digits in a little less that 6 minutes, on 1/4 of a sheet, using pen and paper only. Employing my version of the "long division method". 40.39061 You too could learn to do that if you applied yourself. It only takes the ability to add, subtract, and multiply efficiently.
+Naae: If growing up having gained some tools with which to think, makes me a "nerd", I would rather be a nerd. How is being dull witted working for you?
![I.N "HALLUCINATION" | [Stray Kids : SKZ-PLAYER]](http://i.ytimg.com/vi/n5B5q1Hwt_U/mqdefault.jpg)
10 million views! Thank you for making this one of the most watched math videos on RUclips!
No problem!
It was very interesting. Thank's you too !
Thank you
what's hilarious is i started being teached cube roots today and got this in my recommendations
Congrats, and well deserved
Does it still work after the latest patch?
savage bro
You'll need to check the patch notes bro
@@thepungodThanks, I'll ckeck them.
Why did I laugh so hard at this 😭😭😭
Patch 2019.04 only did bug fixes, so maybe patch 2019.05 will change something.
Love how the thumbnail misleads you to think you can just take the first and last digit to get the answer
@Dawson Posekany LoL yes that’s why I clicked the video
I almost skipped the video like just take the first and last digit but no it's not that at all
Me too
Really
Cube root of 8 is 88
I hope this doesn't get nerfed
The heard the developers are going to nerf it, sadly.
Mine doesn't work, have I missed an update?
Rayan Rashid in the patch notes a buff is coming at the end of the month
Unfortunately, in version 20.2 (coming January) this trick will be patched, but hopefully there are some bugs in the system that let us still use it
Caution: this works only when you are asked to calculate cube roots of perfect cubes. Don't brag anywhere and fail if someone asks you cube root of 2198 and you say 12 (using this method)
Because I know that actually the cube root of 2197 is 13 so 2198 is 13.0...1
It is an estimation method
“You first have to memorize the cubes of each number from 1 to 10”
nevermind
Mooddd😂😂
thumbnail, can't memorize ten numbers, finishes with NEVER mind. God bless this youth.
729 is the only weird one, really. The rest just make sense.
*forget it* 🤣
@@thedeekabides how 729 weird?
"If she knew this trick she would have answered 5^3 very quickly"
Step 1- **Memorize the cubes of numbers from 1 to 10**
Well he's technically correct
😂😂😂😂😂😂
"Quickly"
i dont know if you should be in a high authoritative position if you can't figure out the cube root of 125 in a reasonable amount of time.
E_M_E_T Eh, dunno about that. You can be good at your job without knowing maths. This kind of knowledge doesn’t defines someone’s intelligence and ability to do their job well. It’s like knowing countries’ capitals; there isn’t really any merit in learning this kind of stuff by heart. Cant judge someone’s intelligence and abilities based on that.
My teacher thinks I am a genius. What she doesn't know is that I was actually using this trick
"She " Woah nice job
I can't explain how i got it though :'D
@@tot0N what
same here
xd
But its fake
My method: literally memorizing the answer to every problem I’m asked. It comes in handy especially in Calculus
you scare me
You have a power beyond anything we mortals could ever imagine
Yeah lmao I remembered when I memorized that the cube root of 11 is 1331
@@Sartfla I think he meant the cube root of 1331 is 11. Just a small mistake
@TIV67 Playz I hate trolls like you😂😂😂
Next video how to calculate RUclips recommend algorithm
😂😂
😆😆
Impossible
Absolutely impossible!
Best
I have a math degree, worked with numbers my entire career. I’ve never seen this before, it’s very interesting. I love math, in school I would make up my own problems and solve them.....for fun.
I’m helping my 10 year old grandson with his math homework and will show this to him. It may give him a leg up on his future classes.
These are quite common vedic tricks in Indian education specially among students preparing for competative exams as we need to be very fast in our calculations. You can look for other tricks too in youtube.
I never had math homework until middle school so fine
This does not in any way help solve any math problems. It is just a neat memorisation trick.
I like math and physics but I realized that I'm really bad at teaching math. Whenever I try to teach my little sister or my friends, they always have trouble understanding. But I am not that bad at teaching (explaining) physics' concepts/theories.
Wow, grandpa with a ton of knowledge of math. Respect sir, hope you doing well in your old ages teaching your grandson
Other Students:Whats tha need??We have calculators
*_Indian students:Give this man a Medal_*
That explains myself as an Indian. Thanks a lot.
I wonder they allow students to use calculator in exams 😲😲
Kash india me bhi aisa hota
@@anusangeet1869 in higher education you can use calculators for calculations since the problems are big. Lower grades don't need it coz problems are too simple and most probably you won't come across a cube root of 7 digit number there.
@@souravkb par hamare liye to woh problem bade hi hote hai bhaiya😁😁
😂
I'll give you two interesting things I learned on my own. If you add every odd number starting with 1, no matter where you stop, you will have a perfect square. Also, if you wonder if a number, no matter how large it is, is divisible by 4, 8 16, 32, etc. take the last 2 numbers and if they are divisible by 4, the entire number is divisible by 4; take the last 3 number and, if they are divisible by 8, the entire number is divisible by 8, etc. I'm sure I'm not the first person to figure these things out but I was surprised when I learned them.
Also if the last digits are 0, it will be divisible too, like 500 is divisible by 4 because last 2 digits are zeroes, 5000 is divisible by 8 because last 3 digits are zeroes.
You always learn something everyseconds no matter its important or not
its called divisibility criterion
@@user-yx4pb1zk2t I don't know about divisibility criterion. I just found it by accident one day. The square root thing I discovered when I was taking an online IQ test. It gave the following: "16, 25, 36 . . . What is the next number?" I looked and saw 16 + 9 = 25 and 25 + 11 = 36. My response was 49 which was correct but for the wrong reason. It didn't hit me that those numbers were perfect squares. I then followed the rule I came up with and found that it was correct.
that is pretty interesting
It’s sad how the secretary of education can’t remember the cube root of 125
Kinda infuriating as a student ;-;
she probably did know but was sticking to her rule of never answer math questions on tv. if she started answering easy questions, she’d eventually start being asked harder questions, and when she refused to do them, people would assume she didn’t know how even if she did.
5😥
@@sr.braydondo huh, I'll use this logic for my next exams!! Wish me luck
Jesus said "do not try to remove a spec from thy neighbor's eye when there is a log in your eye"
And these teachers out here like: ( 🌳 _ 🌳 )
I impressed my parents for the first time, yessssss.
Walking Meme L O L
Worldwide Handsome sub to me lol
@@Sopotastic No lol
@@vunniee ok lol that was 2 months ago lol
@@Sopotastic ok lol
I'm finally happy that RUclips for ONCE has recommended me something useful👏🏽👏🏽
😂😂😂😂😂😂😂😂😅😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😅😅😅😂😅😂😂😅😂😂
Lmao
lol
ruclips.net/video/PkKAHroBTtA/видео.html
How to time travel
More like your happy you understood this XD😂🤣
I remember doing this technique when taking a test back in highschool, way before I got into string physics and higher dimensions. I believe it was an exam actually, that consisted of 10 cube root equations to be solved via paper and pencil (show your work). I used this technique mentally, only writing down the table because I had to show work somehow. Couple of minutes I’m the first one done and my teacher is in awe. Feels good
sure
You have an exam of just doing cube root equations?
You do not just get into string physics
What did string theory have to do with this lmao
And then everybody clapped.
Remember: This only works if the number to be rooted is actually a cube of an integer. Thus, the title should better read "How to calculate the cube root of cubes of integers"!
I think the thumbnail is far worse than the title, don't you agree?
@@fahrenheit2101 Omg so true
integer and between 1 to 100
Yes. 🙄🙄🙄🙄🙄I am trying other number but I got wrong now I came to know 🙏
I figured that out the hard way
What is 1+1?
I refuse to answer any math questions on TV.
😂😂 Exactly
Is math related to science tho?
@@BloodHoundPL Science without math is like car without engine
@@reduanbadhon6346 lol maths is the father of sciences
@@lordx4641 do u even understand what I said?
"Ask someone to pick a number 1 to 100"
My grandma: 1
Богдан Седин must be 11-100
Hahaha
Now is your chance to impress her by knowing the cube root whilst juggling oranges
Nice one
She doesn't want to bother you
I enjoyed your cube roots solving techniques. Great presentation.
I never knew it was so easy after seeing your resolve.
Thank you sir.
Teachers that want you to show your work disliked this video.
This was in my math book itself.
Sebastion Stan Well lucky you
@@-cookiezila-461 we got this in our mid-semester (50 Marks) exams in July 2019. for 3 marks, we had to explain all the steps. I'm in 8th Grade.
That is my math teacher
Tell your teacher the trick then smart one
When the youtube algorithm is more worried about your future then yourself
I don't have a future
I have never in my entire life liked an educational video before, but this was really helpful so thank you soooooooo much
I think even memorization is too hard for someone who doesnt know the cube root of 125.
@FlyingMonkies325 So in your next post detail the steps you would take to find the cube root of 10 to seven places. (-; Btw, if humans and animals couldnt memorize, they couldnt exist.
@@37rainmanyou are right People think they have to oppose an opinion even if it's correct. 🤦♂️
cube of 125 is 5
so easy
@FlyingMonkies325 you literally wrote an essay
Its 6
Only works for perfect cubes, obviously.
Chris Horne Ikr Yeah...
For sure. After the first example I immediately tried to find the cube root of the earth circumference of 24,896 using this method and it didn't work. I'm not impressed.
@@SaturnStarOfDavid this might get patched in the future though.
Also not for more than 6 digit numbers
+douglas: What he meant when he said that is that the ability to find the cube root of a perfect cube is obviously perfectly useless
One can just as easily teach oneself to find the cube root of ANY number, to ANY accuracy desired. What is the cube root of 23.692, rounded correctly to 4 digit accuracy? You can learn to arrive at the solution in a few minutes. 7 digits in perhaps 8 minutes. With pen and paper only.
Ask someone to pick a number 1 to 100
Imagine they pick 636,056
Something aint right
lmao i didn't notice earlier
57x57x57= 185193 but 3 is the end of the number and it’s between 5 and 6 but it’s 57
@@Datisfunny When the last digit is 2,8, 3 or 7, you have to consider the 10's complement of the number i.e. 10 minus the number.
So it does correctly arrive at 57
I forgot to change my comment I forgot 7x7x7=343 so the end = 7 and the front = 57 so it is 57
The answer is 86x86x86 is 636 056
I used to actually know this trick, although i did it with square roots. I had no clue it could work with cube roots too, except it was slightly more complicated. You had to do a wierd subtraction thing from the first digit and i forgot exactly how to do it but this is way easier and more impressiveThanks!
And this came in my recommendation after 5 years!
For u only 5 yrs but for me 5 yrs 1 week😏😏
@@rohithreddy140 😂 you're funny
ROHITH REDDY for u only 5 years and 1 week but for me 5 years and 3 weeks
@@siuuuuu8973 lol,just u copied my thought
looking pretty fly Moli, ig - @_oli.wright_ x
i liked the fact that you edited a hand in rather than actually writing even though it would be easier in every way.
what's the fun in that
Matthew Smith Actually, there is a website to do this. Its pretty lazy.
Anonymous Someone name?
Darwin Watterson There is many, but one that looks like this one is moovly.com
I used to use it back in middle school.
Darwin Watterson numberude- rootstorm
Q: So, when would this be useful?
A: When flexing on your homies
LOL FACTS
Now all I need is another video letting me know how to tell that the number is a perfect cube in the first place so I know when to apply this.
But 125 is easy! 5x5=25 is not hard, and 25x4 is 100 so that helps you remember 25x5 is 125.
That's the only one I could have been able to get right because it is so easy.
@@ammaleslie509 all the smaller numbers are easy but that’s not what I was saying.
If you don’t know that 39304 for example, is a perfect cube then you can’t apply the trick.
@@creaty2852 That's what I was thinking about... Simply relying on this trick will get urself tricked and propose a seemingly correct answer. I suppose the most secure way is to use Taylor's Expansion
@@composerlmythomorphic2635 What's Taylor's expansion?
good
still, 125 is just absolutely elemental
+DashRogue yea its even a prerequisite for this technique :P
DashRogue I'm not gonna like this comment, since it has 125 likes.
DashRogue yea. It's like 2x3: you don't need to solve it in your head; you should already know it.
Who ever say that you have to be smart to run the US Dept. of Education
+Baba: Naïve. So what you are saying is that you are "smart" if you know that 5 cubed is 125? Btw, she was not there to be quizzed by little children about basic math. I would have simply said to the brat, tell me the cube root of 300, accurate to 6 places. I can do it, you cannot -- run along now, and take your parents with you.
Who are getting this in their recommendations after 5 years randomly lol
Help... Lol
I wanted this video and youtube can read my mind...
@@dianatotova6888 love is real
.
.
.
.
or is it?
Same here
6 it is
Hiring manager: what is your edge among othe applicants
Me: I can mentally calculate cube roots of any perfect cube number
Grrrr!!! I need a head manager, somebody to manage my head while I am forgetful.
Only useful till 1-100 though
i dont think ANYONE realizes you said that with cynical laughter!
*upto 100
@@RandomGuy-vq3gd I found that it can be used to find 1-1000 it’s not 100% accurate but then u just have to use logic to get the middle part
My coaching classes teacher taught me this trick but it just went over my head. Thanks for explaining properly.
WHY COULDN’T YOU EXIST WHEN I WAS DOING NS IN HIGH SCHOOL?!?!?!😭😭🤣🤣
Dont worry,in next life we will use that
Ey it is in ncert text book of class 10 th or 9 th - estimation method 😂😂
@TIV67 Playz I think you’re in the wrong comment section buddy
@@rythmplayz He's on the wrong website
@@theweirdwolf1877 Yeah
RUclips: You hate math right?
Me: yeah.
RUclips: here.
Y tho :/
Dope nyan Cat
Undefined
@Dope nyan Cat ask Siri about it
Dope nyan Cat 5out of 0? = -5
@Dope nyan Cat i ask you friendly to remove this comment!
In my experience, using Newton's method is usually better, especially if you don't know if it's a perfect cube.
The trick for cube roots with Newton's method is to make a guess (I usually go with powers of 10), then divide your number by the guess twice, add the guess twice, and divide this by 3. This will give you a much closer overestimate.
For 636,056 a good guess would be 100.
After you divide twice you get 63.6(056) (you can round to make it easier to do in your head).
After you add twice you get 263.6.
Divide by 3 to get 87.8.
Since this is an overestimate, round down to get 87, which is only one off. (If you repeat again you'll get 86.)
The same trick works for square roots and other roots. For square roots, you divide once, add once, and divide by 2. For 4th roots, you divide 3 times, add 3 times, and divide by 4. etc.
Why this is so underrated
i will surely checkout this method
Wow it's so wonderful! How about calculate square roots?
He just released a video on square roots :)
@@user-rh7nd5xv7y Please give me the link, thank you
@@luisdato1712 ruclips.net/video/I7TFYa1v9xI/видео.html
I wanted this type of tricks.....11 years ago.....
I wish I can find this.
Cube root of 125
I mean if you did math problems when you were in school the answer just comes to your mouth
You don't even have to calculate
I’m losing more and kore faith in humanity
I think 85
Naïve. She was not there to be quizzed about basic math by a child. That is why an adult would not give an answer to such a childish question, in such a setting.. If you don't realize that, you are likely a child.
ronald dump ok "Ronald dump" even if she wasn’t there to be quizzed, it certainly looks worse by not doing the problem then doing it and entertaining he child.
You can just say 5 is 5 and last three digits go away. The answer is 5.
First time seeing that education channel hit 1.82 subscribers
Congratulations keep going
This is going in my playlist.
how do you work out the cube root of 4364
+Heily Kohestani The number 4364 is not a perfect cube, it's a bit more than 16 cubed which is 4,096. The method in the video only works for numbers that are perfect cubes. So you need someone to cube a number and then you can extract the root.
+MindYourDecisions So how to calculate the cube root of a number which is not a perfect cube?
And what if the number _is_ a perfect cube, but it has more than 6 digits?
I know some people (e.g. Shakuntala Devi) who can perform such calculations mentally, and tell the sequence of decimal digits to whatever precision you ask them for, but they don't reveal how they do it :/
+Bon Bon shut up, you are annoying.
How can I know the perfect cube it or not? - to apply this method... And what practical application, if I can not know a priori, the perfect cube it or not?
Y10Q Be nice, he was asking a question. Not everyone knows this stuff. I'm new to this method.
Tried this the other day. Couldn’t get it to work. I think god patched it.
Only works for perfect cubes.
+Abrar. And thus is perfectly useless.
Copycat
DaDanMan Guy I’m not a copy cat I assumed it worked again in the recent update but clearly it’s been patched again that’s all I’m saying. I’m helping people not waste their time lol
ronald dump not at all, it’s still a cool trick. Try to be optimistic and not negative all the time
Omg that's sooo cool, but like it's easy to forget
Ayailyasfatima 3 that is why you have to remember
Jaden Tran yeah but after you stop practicing you’ll forget
Ayailyasfatima 3 nice said..
The cube root of 42,875 is 35, not 45.
Lol!!!
Thank you so much Sir
I'm in 10th grade.
This will definitely help me bcoz we are not allowed to use calculator in exams. Thank you again....
❤️ Love from India 🇮🇳❤️👍👍👍
For people who say “never if I have to memorize 1-10(rules) I’m out” I can basically throw the statement back to you, how can you memorize a whole fu- 3 minutes long song and can’t memorize a 20 sec rule?
First Name tuff
Book Loon tuff to memorize a 20 sec thing?
I can already smell you
We just don’t want to memorize this?
And we’d rather learn a song that we happen to play over an over?
Like, I get where you’re coming from, but.
Can0Cringe #706 laziness. Got it.
I tried it on the number 1024, assuming I followed your instruction correctly, I cam up with 14. But 14 cubed does not equal 1024. Can you tell me what I did wrong?
+Tamara Enyart The number 1024 is not a perfect cube, it's a bit more than 10 cubed which is 1,000. The method in the video only works for numbers that are perfect cubes. So you need someone to cube a number and then you can extract the root.
Thank you. Not sure what a perfect cube is. I haven't been in school in over 30 yrs. Is it similar to a division without a remainder?
A perfect cube is the cube of a whole number. Or that it's cube root is a whole number (without any fractional part). The cube root of 1024 is between 10 and 11, so 1024 is not a perfect cube.
+Tamara Enyart A perfect Cube is like a perfect square. Like 36 is a perfect square because you just need to multiply 6x6 together. So it's any number that is the same number multiplied twice: 2x2, 4x4, 5x5...NxN.
Anyways, a perfect cube is like a perfect square, except it's the product of three of the same number: 8 cubed is 2 because 2x2x2=8 and 125 is a perfect cube because 5x5x5=125. SO 2x2x2, 3x3x3, 4x4x4....NxNxN.
a times a times a = perfect cube, if and only if a is a number with no decimal points (integers). For example, 10.08 x 10.08 x 10.08 is not a perfect square, because 10.08 is not an integer.
At the 185,193 example
185 is closer to 216 than to 125. So why is it 5 and not 6?
I don't think I understand what "without going over" means.
EXACTLY!
it only goes over 125. it will count as 216 when it is equal to or over 216
Broockle Well, actually pick the lowest number which the 185 in between with. Going over means above the 'in between'.
Psyto x
o that's what he meant. I get it, thx.
James Reilly
uhm.... that's uh.. wat? xD
Alprimez
So it should be in the proximity of the highest next to? Sounds reasonable.
Broockle without going over means not to be over the number?
If I'm being honest this is very useful because they didn't teach us this in pre-cal and it makes so many things so much easier especially if we aren't allowed to use our calculators.
0:05 idk why but that made me laugh so hard 😂😂
Anushka Gupta what happened in 0:04? Could u be more specific?
@@juliuskang7937 "Why would you ever wanna do this?"
title should be "how to calculate cube roots of numbers you already know are perfect cubes in your head"
Whenever I stand at the supermarket checkout, I wish to be able to work out the cube root of all the prices. Thank you for this great help in real life.
At the begaining when I learned the computer, every time I did something wrong, I hoped I could replay.
Other Students: why should we care , we can use calculator
me an indian : thankyou master for this useful information
i am indian
Man teachers itself will teach the method.btw I am indian
@TIV67 Playz some people believe in Jesus, some don't, if you force them, they end up hating you and the religion.
@TIV67 Playz Ok but like what’s the cube root of 328509
@@xarmchia7750
39 obviously
This is a fantastic video. It is useful, practical, doable, learnable and impressive!
okay, now i will write this "formula" on the end of my math notebooks
Finally someone is thinking like me 🤔💭🤣
oh.....i got it....
thanks for helping us in math....
slegnbvc
Yup! Now I don't need to look for my TI-83 everyone I get maths homework! Wait..
Okay. The method does not work on everyone
Try 49305
Samuel Papp thabks. I got that
You made a good niche for yourself Presh with your math channel. I'm sure you're raking in the big bucks too.
Crikey, Presh: You astonish me often, but particularly so this time. Who'd'a thunk it? And I have two questions:
1) How do you come up with these ideas/solutions?
2) What software/editing app do you use fo that truly sweet handwriting thing?
I have to admit that I'm in love with that penmanship thing.
Thanks. Per question 1, I read about Nicky Morgan and wanted to make a video. I did some research and found this cool trick--if you read the note it's a very old trick, it was actually published in a 1913 newspaper article!
Per question 2, I'm planning to make a video on how I make these videos. There is software that I am using, more details to follow.
MindYourDecisions Hey man! I love your videos, just curious if you happen to have made that video on the software you use? Thanks!
This pops up in my recommendations right when I needed it 😂
Hey Presh Talwalkar, thank you so much for taking the time and effort to produce this excellent, easy to understand, video tutorial on how to quickly calculate the cube root of a number that is capable of such without fractions. Keep up the good work!
The cube root of a number that is not a perfect cube would be irrational. Infinite decimal places, not a fraction. But I'm just knit picking. I also enjoyed the tutorial.
This is vedic math trick
You are the best youtube channel İ have ever seen
what if the number goes past a million, like 1,016,139
we keep 9
9
then we ignore last 3 digits getting 1,016
it goes past a thousand, so what do we do there
Memorize more cube roots, like of 11, 12, 13, 14, and so on
1016 is closest to 10 so it is 109
Justin Norman All you would have to do is memorize even more cube roots so instead of memorising 1-10 memorize 1-20
the cubed root of 1,016,139 is 1,016,139^(1/3)
simple.
109*109*109=1295029 can you explain me that?
Okay now get off my recommended list
Abner Lowe lmao fr
Abner Lowe - 239 likes but only two replys. Come on guys all least say something.
Abner Lowe Hello
LMFAO same 😂
Abner Lowe mean
In my recommended November 2019, Anyone Else?
I was doing calc homework when I saw this vid.
Yeah lol
Strawberri Senpai what grade do you do this math?
@@Mohammad-wr1sc highschool Junior
Ye
Woah!!! nice trick, simple but easy to understand.
Probably the most useful math video on the internet. Easy to understand and incredibly useful. It’s just weird that they don’t teach this at school
its not that useful because it has to be an integer
It doesn’t work with every number so not worth learning
isnt 185 closer to the cube of 6 than to the cube of 5 in the example with the cube root of 185193?
because 185 is 31 less than 216 (6^3) and 60 more than 125(5^3)
Akira Nishiki The algorithm is to round down when you're between two numbers. (In the video I wrote closest cube without "going over" by which I meant to round down).
oh ok thanks for the quick respond :)
+Akira Nishiki yep
+Akira Nishiki 185 isn't 29 less than 216, it's 31...and 185 isn't 40 more than 125, it's 60...learn maths and then watch this kind of videos
haha wow, i failed there :D
no need to be rude though. also it would be weird, if educational videos were for the intelligent elite only. asking questions can´t ever be wrong, especially if you were dumb. Being offensive to the less intelligent won´t make them smarter, spreads hatred and is just dumb. You don´t need to hurt others with your words just to feel better.
Just give it a try, everyone makes mistakes :)
I´ll edt the post, also the main question and problem i had would have stayed the same, but was already answered ;)
It only works if you know the number has been cubed though
Yes exactly. Although the more practical method is harder to understand and apply without a calculator
It can be useful to have un idea of the size of the cube, comparing the last two or three digits with the cubes of the numbers from one to ten.
@@musenw8834 really? Just do Prime Factorisation...
@@sebastianstan9655 I meant for bigger numbers. Preferably those above a billion or so.
@@musenw8834 calculators.
that is awesome, now i have just to learn by hard and it is nice to recover that channel. it was recommended to me in summer 2020. I forgot the name of this channel but i found it again and it is awesome
wow! this is totally removing the use of school! All I need to do for education is go on the Internet and search it all up then I return Doctorate
So the cube root of 39,304 is the same as the cube root of 39,204?
NƎcktie3223 its 33.97 if thats close enough but 39204 isnt a perfect cube so its not gonna be a whole number
***** In other words, they don't have the same answer.
They don't, but you are purposely starting with a number that doesn't have a nice clean cube root. This trick assumes that a person takes a number between 0 - 100 and cubes it, and then you cube root it in your head. To pick an arbitrary random large number would be cheating at this game.
That's working in the other way around of what I was thinking.
he said "have your friend cube number in calculator" that means that trick only work with perfect cube. if u just random the number, it wont work.
For anyone who's wondered why the cube root of 185,192 is not 58, it is because this trick only works with cube roots that are whole numbers.
You're right, it isn't 58. It's 57, like the video said, and 185,193 is a whole number.
Newes Gam and its 185,193
Miguel Patino it's 57 and that's a whole number
Thank you. This is a wonderful video to find cube root of perfect cubes.
Most important part is... to remember the numbers. So 1:28 is the main point of this whole video
I can finally pickup some chicks now with this trick
@@sasmitvaidya How are girls who study English bitches? I prefer stem myself. But just want to see your point here.
What kind of fight is this without any hot topic.. oh sorry there is one.
Because girls in the physics class typically have more brains in their skulls.
NPC Girls who study English are hotter but more stuck up
@Aryan Dewan this is like a code I wrote once
as long as you know the result is an integer
If I’ve already memorized the whole number why would I have to spend additional time memorizing the last digit of that number?
I think it helps for large numbers. An easy way to remember is by drawing a picture by connecting the numbers on the phone dial. It forms a mirror image of itself and it's really simple to memorize it thereafter.
@FlyingMonkies325 Sir, the point here is to find the cuberoot of a number, not the cube of it. You cannot use the method you suggested to arrive at the cuberrot of a number. Sir, here is a number: 479,321. Now, in the next post detail how you would find the cube root of it using your method, or the guy in the vids method. The proof is in the doing, not the yadda, yadda, yadda
U got the point I was thinking about
U got the point I was thinking about
Visit my channel dear
Thank you so much sir, it is just amazing to calculate any cube root instantly lots of best wishes to you.....
It's very easy and useful .thank you so much ☺️
How good is his handwriting?
D S that is animated -_-
nmnsud he knows -_-
Jk
D S 😂😂😂😂
P good.
OMG HOW COME AM I SEEING THIS JUST NOW??? THANK YOU SO MUUUCH
This is the type of thing that got me interested in math as a kid! I love it!
And then your friend was shocked that you memorized the cubes from 1 to 100.
Started to think you are a weird person.
Ain't nobody got time to memorize that table.
Or idgaf about cube roots?
+Odrigoray I don't either, why are we watching this lol
Odrigoray you just lazy and have bad memory, it only take 20 minute.
You're right, I am lazy.
I do
If you are over 12 years old, and you can't figure out the cube root of 125 in less than 10 seconds, you are really bad at math.
Ulises Weroleytor k
I suspect she didn't want to answer because if she did people would ask her increasingly more difficult math questions. That being said some people really are that bad. An ex boss of mine spent 5 minutes looking for a calculator to work out 5+8. Another asked what I was doing when I used long addition on a piece of paper, I actually had to explain the concept.
So how would you work out the answer? For those of us that are actually bad at math.
Grant H . 25 goes into 125 5 times, the square root of 25 is 5. 5x5x5 is 125. See?
Trevor Mccord Never understood how you'd work out 25 goes into 125 5 times without having memorised it, to me it's just trial and error until I figure it out, no real method.
I’m in grade 8 and haven’t even learned Cube roots, but this is gonna be very helpful when I go to higher grades
@@meg_8518 so?
@@meg_8518 Ok.
@@meg_8518 I took a test back in 5th grade to see if I could skip to 7th. I ended up going through the entirety of high school during my middle school years and got to college at 15. After graduating at the top of my class at M.I.T and studying theoretical quantum physics on my spare time, I am sad to say that I can't figure out who asked
But u learn cubes and cube roots in 8th grade...
@@theweirdwolf1877 I guess different countries’ math teaching speed is different. I’m in Canada and I moved there from Hong Kong, and Hong Kong math is taught 2 years faster than Canada math, so I’ve already learned most stuff in grade 8 and I was supposed to learn cube roots in Hong Kong grade 8
This really helped me... Thank you so much!
This was actually useful 😭 thank you!!
If you like please SUBSCRIBE AND SHARE
ruclips.net/video/2jf5zdkDB80/видео.html
WAIT A MINUTE!!! ON 4:04 the answer should be 67 because 185 is closer to 216 than 125!!!!so therefore, this trick does not always work!
no the rule has "...without going over"
lol
WAIT A MINUTE!!! You're completely wrong.
RonyTV/RTV WITHOUT GOING OVER
RonyTV/RTV easy
I love your videos, they helped me much in the olympiad
this is great solve from Japan
sugoi arigatou gozaimasu
thank you
YAAAAA MAAA TOOO
Btw this formula is from India
Why is this RECOMMENDED to me during quarantine
What if we have 7 digits number ? It also works in same way for 7 digits number ?
You can learn to find the cube root of ANY number if you like. The material in the vid will not help in any way.
Here is a number: 65893.28. I just evolved the cube root of it rounded correctly to 7 digits in a little less that 6 minutes, on 1/4 of a sheet, using pen and paper only. Employing my version of the "long division method". 40.39061
You too could learn to do that if you applied yourself. It only takes the ability to add, subtract, and multiply efficiently.
+gamer: Actually sitting in mommys house playing vid games is the epitome of being a "nerd"
@ronald dump, you seem like a nerd tbh.
@@ronalddump4061 - You're thinking "loser". Nerds tend to grow up rich and successful if they keep going. e.g. Bill Gates.
+Naae: If growing up having gained some tools with which to think, makes me a "nerd", I would rather be a nerd. How is being dull witted working for you?
This is really fun and great idea! Iam sooooo trying it!
U r GENIUS MAN!!
Thnx a lot!
Helped me
Q: How to Ans any cube root of a number..
A: Memorise it 😂😂
That’s how I would go from the perfect cubes from 1^3 to 20^3
"memorize the cube roots from 1 to 10 "
me: hell nawh *exits vid*
***** the education isn't even hard. It was joke if you didn't understand
go watch your fucking gay youtubers
it is
why?
***** you could have ignored it but nooo you had to be triggered
I knew this trick as it is Vedic Maths.
Well explained !!!