Giuseppe Jones 1: Don't start sentences with "but", it is bad grammar. 2: *you're not a genius, you're probably as smart as a turd and uglier than one too. 3: You managed to make 5 grammatical errors in one sentence. 4: I do not know why I am even commenting back to you.
Thank you so much. My teacher gave me homework over vacation using our textbooks to teach three weeks of work to ourselves! Needless to say I don't understand it just by reading it, so thank you for explaining!
Thank you so much!! I've been trying to figure these out for days. My teacher taught the same things, but for some reason how you said it just made all the fog clear.
thank you khan, now it's a lot easier to understand guassian ellimination. We were told about guassian ellimination in class, but it was like looking to deep deep scary forest for an hour :D thank's a lot!
When my teacher explained it, i didnt understand much. But this vid helped me a lot. Thx, your doing a great job. Just wanted you to know that we appreciate your work here in Norway aswell.
For anyone who uses an voyage 200 or an ti-89, you can use the function rref (reduced row echelon form) with the augmented matrix and the function will do exactly what he does here, using gauss-jordan elimination :)
+TheSamuraiApocalypse He used an annotation to say it should be 2, not 4. I usually keep my annotations off because other users use them for ads and other annoying junk. I haven't seen Khan Academy do this.
For anyone that is confused this is done to eliminate the x coefficient in both Equation 2 and 3, and the Y coefficient from Equation 3 doing so makes solving for z as simple as dividing the multiple of z by what is on the other side of Equation 3 then you put what z is equal to into equation 2, allowing you to solve for Y, finally you are able to put both Y and z into Equation 1, which gives you the solution
@zryda07 There are 3 EROs: 1. You can add a multiple of a row to another row. 2. You can mulitply a row by a non-zero constant. 3. You can interchange two rows.
I'm giving a problem like this to my 4th grade Math Olympiad class. It doesn't include variables, but instead geometric figures. I followed the instructions exactly as he explains, and it worked like a charm. The problem is that there's no way that this problem was meant to be solved this way by 4th graders. I don't ever look up answers to problems for this class, so once I see the explanation given, I'm sure I'm going to see a very clever solution that doesn't include Gaussian elimination.
In these older videos, Sal sounds as if he has just got out of bed and is in a pleasantly groggy state, and is like "aaah, yeah, that video - let's do it...".
Nice one. I'm gaining a lot of intuition about the linear algebra topic which I know I'll be able to use as I'm a computer programmer in the 3D graphics business.
This is the same as just solving simultaneous equations algebraically in the way I was taught at secondary school! The only difference is substituting the letters with a position on the grid (i.e. row 2 means y). Is there a case where this is significantly more convienient than merely applying this 'algorithm' to the equations themselves? Thanks.
Unless you fool around with Gauss-Jordan/Gaussian elimination all the time an error like -(-2)=4 is easy to make. As you say, this stuff is computationally intense, and it's also deceptively complex. 5 stars, good job.
in the last video, you said there can be 2 points of contact if there are 3 equations. Here, there are 3 equations but how is it possible to get 2 points of contact. Like how would the answer look like? example (1,2,3) and (1, -2, 3)? just a negative on one of the x or y or z?
The only thing I don't like is that you put the simultaneous equations into a matrix, reduced the matrix, and then put the reduced matrix back into simultaneous equations to solve. You could have just done that in the first place. I would recommend that you keep reducing the matrix into the reduced row echelon form which is the identity matrix. Then you have it solved in matrix form. Putting into equation form is only useful when you have a rank deficient matrix and thus have a free variable.
would i get the same answer if i got rid of the 2y from the 3rd equation by multipying the first equation by -1 and then adding that result to equation 3?
***** Yes you would basically use the same procedure, it would just be very computational. Your best bet would just to use matrices in the form Ax=b where A is your coefficients, x is a vector of your variables [(w,x,y,z) for 4 variables] and b is a vector of your intercepts. Then just do x = A^-1*b to solve. He does this in earlier videos for a two by two matrix.
- (-2) is equal to +2, NOT 4.
Solving for this, you get x = -1
Put that into the original equation: - (-1) + 2(3) - (-2) = 9
Who cares, it's about the method :/
Omg I thought No one else saw it and yes you are correct :)
Put on your notifications, he corrects himselve.
Every body makes mistakes
It's obvious it's just a simple mistake
you're right. my brain was tired. I've added annotations to correct.
Get distracted by Instagram, no i would never!
get distracted by a guy going to eat out (WITH) his wife in his math video?
absolutely.
Hope u people are doing well however it's been 15 years!
I have no idea what just happened.
tbh
It is easy :D
Me neither
"I'm suppose to go eat out...(my wife)" ran through my mind lol.
14:49 for the impatient among us
@@ozzyfromspace among us
Yep me too :D
@@ozzyfromspace thanks 😁
If my teacher was like you I'd be a genius by now
Lobster with Mustard and Rice
but your not genius, your probably as smart as a turd and uglier then one to.
Giuseppe Jones
1: Don't start sentences with "but", it is bad grammar.
2: *you're not a genius, you're probably as smart as a turd and uglier than one too.
3: You managed to make 5 grammatical errors in one sentence.
4: I do not know why I am even commenting back to you.
Giuseppe Jones GET REKTT HAHAAHAA
Lobster with Mustard and Rice I don't go to classes I only watch his videos
Shakil Rahman Giuseppe Jones is just a troll. It is best to not give him any attention.
Man I wish you taught me math instead of my professor
Thank you! Got more than this than a whole lecture!
+Nick Jones-same bro
I love to watch your videos when I'm high. You are very smart, sir.
Thanks a lot Sal, you're style of teaching is so clear and simple, this has really helped me
Thank you so much. My teacher gave me homework over vacation using our textbooks to teach three weeks of work to ourselves! Needless to say I don't understand it just by reading it, so thank you for explaining!
You solve them way more complicated than I learned in the past.
Thank you so much!! I've been trying to figure these out for days. My teacher taught the same things, but for some reason how you said it just made all the fog clear.
thank you khan, now it's a lot easier to understand guassian ellimination. We were told about guassian ellimination in class, but it was like looking to deep deep scary forest for an hour :D
thank's a lot!
I'm living in this man's beard.
When my teacher explained it, i didnt understand much. But this vid helped me a lot. Thx, your doing a great job. Just wanted you to know that we appreciate your work here in Norway aswell.
12:40 "Just for kicks". Oh, stop it, you! Still the man all along, Sal!
Late but I love just for kicks :)
"I'm just writing it in a form that has a little bit less...letters in it." lol, this guy is great.
For anyone who uses an voyage 200 or an ti-89, you can use the function rref (reduced row echelon form) with the augmented matrix and the function will do exactly what he does here, using gauss-jordan elimination :)
Dude, i love your videos :D
I wish i had a teacher like you D;
thanks and keep them coming!
One of the best vids on utube. thanks! perfectly explained.
I love how emphasized the connection with solving simultaneous equations. That made the whole thing click for me.
You are simply amazing! I value your work to the extreme Sal!
How did he get 4 out of -(-2)? Shouldn't that've just been 2? It's at the end.
+TheSamuraiApocalypse He used an annotation to say it should be 2, not 4. I usually keep my annotations off because other users use them for ads and other annoying junk. I haven't seen Khan Academy do this.
Precisely......
Yes, it should be two instead of four
if i saw this two years ago, i'd have passed my exam so easily. good job man!
For anyone that is confused
this is done to eliminate the x coefficient in both Equation 2 and 3, and the Y coefficient from Equation 3
doing so makes solving for z as simple as dividing the multiple of z by what is on the other side of Equation 3
then you put what z is equal to into equation 2, allowing you to solve for Y,
finally you are able to put both Y and z into Equation 1, which gives you the solution
Thanks for taking the time out to help even though your wife was ready for dinner. I'm a wife myself so I know she was starving!! lol
Lol :3
wow you have just brought my love for algebra to a new level. whatever you are doing keep doing it =]
I absolutely love your videos! They are really making a massive difference with regards to my marks for university.
@zryda07 There are 3 EROs:
1. You can add a multiple of a row to another row.
2. You can mulitply a row by a non-zero constant.
3. You can interchange two rows.
God help us
Afrahhussain this shits easy just pay attention
Love this comment. 😌
I'm giving a problem like this to my 4th grade Math Olympiad class. It doesn't include variables, but instead geometric figures. I followed the instructions exactly as he explains, and it worked like a charm. The problem is that there's no way that this problem was meant to be solved this way by 4th graders. I don't ever look up answers to problems for this class, so once I see the explanation given, I'm sure I'm going to see a very clever solution that doesn't include Gaussian elimination.
Very helpful for linear algebra clarifications. You are gifted.
Thankyou sooo much , you have really made a difference to my studies.
wish i had this guys brains for my exam tomorrow!!
Thanks for another great video!
Just used this to help me solve an electrical engineering problem for uni. Hurrah for Khan!
My favorite part........when his wife called.......from downstairs
😂😂🔥🔥
Fantastc video, thanks heaps, you’re amazing.
Thank You a lot, You helped me understood this thing..
15:23 he is getting laid.
So honey, at what point do you think our surfaces will meet?
14:57 more specifically, he is planning to, ''eat her out''.
Harki Singh dude he said his wife is downstairs and he is going to eat out. HE IS GOING TO EAT HER OUT
Tq sir lucid explanation....liked & subscribed
Careful sir x= -1 ;) And thanks for this amazing content
In these older videos, Sal sounds as if he has just got out of bed and is in a pleasantly groggy state, and is like "aaah, yeah, that video - let's do it...".
Nice on bro, u re a genius. A quick observation though -(-2)= +2 not +4 when solving for x. But thanks for your efforts.
Nice one. I'm gaining a lot of intuition about the linear algebra topic which I know I'll be able to use as I'm a computer programmer in the 3D graphics business.
Thanks for the explanation Sal.
which intuition video that Sal just mentioned ?
I love your idiosyncrasy
this helped me a lot thanks :)
nice, ive been having such a bitch of a time lately since i totally zoned out for my last 3 classes. good video, im on top of things now
This dude is the best !!!!!!!!
Got it. Thanks Khan. 👍
This might help kids and good job sir :-)
You are awesome!!!!! Please come and teach in Hawaii!!!! PLEASSSSSSSSSE!!!!!!!
T was kinda funny wen he said he has to go have dinner with his wife 😂
Thank you sir! Easy to follow!
This is the same as just solving simultaneous equations algebraically in the way I was taught at secondary school!
The only difference is substituting the letters with a position on the grid (i.e. row 2 means y).
Is there a case where this is significantly more convienient than merely applying this 'algorithm' to the equations themselves?
Thanks.
Unless you fool around with Gauss-Jordan/Gaussian elimination all the time an error like -(-2)=4 is easy to make. As you say, this stuff is computationally intense, and it's also deceptively complex. 5 stars, good job.
Still the best😭 thnx from students of Shyngys agai💘
Tthx alot...
you r a great man.
wow this video really helps to understand them. thanks
Sal khan is the man!
shouldnt x be -1
Awesome
So easy way
Thanks
+Khan Academy why is the next video not working? the one were you introduce us to vectors. it says its private. hope it gets fixed soon :)
what about the elementary row operations? I never saw you interchange rows or explain those laws.
My teacher gives us extra credit to watch these videos! :)
THANK YOU SO MUCH!! i finally understand this shit!! why cant you be my lecturer!
When it comes to eliminating "6".. Can I use the first equation? Or you always have to use the second equation?
in the last video, you said there can be 2 points of contact if there are 3 equations. Here, there are 3 equations but how is it possible to get 2 points of contact. Like how would the answer look like? example (1,2,3) and (1, -2, 3)? just a negative on one of the x or y or z?
You are the real MVP ;)
thank you so much this helped a lot!
14:53 the solution is omg my phone is ringing. I KNOW ALL THE MATHZ
What do you do when 2 of the points are the same because one is a toppoint and the other is just a given point?
nice informative video
How do I find out how to solve two equations with two unknowns?
I know I'm like 6 years late but if for some reason you still haven't figured it out, check out simultaneous equations before u get into matrices
The only thing I don't like is that you put the simultaneous equations into a matrix, reduced the matrix, and then put the reduced matrix back into simultaneous equations to solve. You could have just done that in the first place. I would recommend that you keep reducing the matrix into the reduced row echelon form which is the identity matrix. Then you have it solved in matrix form. Putting into equation form is only useful when you have a rank deficient matrix and thus have a free variable.
It starts at 3:30
@ 01:27 were did u get the 3 from??
why cant you be my teacher for all my subjects :(
your mind is working faster than your hands and tongue as well!i noticed what about you?
how did you get the 4 in (-x+6+4 = 9)? isnt the 4 suppose to be a 2....
would i get the same answer if i got rid of the 2y from the 3rd equation by multipying the first equation by -1 and then adding that result to equation 3?
why -(-2)= 4
how about equations with 4 unknowns like in the Lagrange multiplication?
-x+6+4=9 how did -z which was -2
Became 4???
I didnt understand ....
Did u multiply it by 2? Again??
It wasn't supposed to. That's an error. In the end the answer should be the point (-1,3,-2) not (1,3,-2).
You should make a video on solving two unknowns and two equations
boi...
Ntnsity what
Still saving me on a Precalc Test 16 years after making the video
is it possible to solve equations with 3, 4, 5 or even more unknowns with matrices??
***** Yes you would basically use the same procedure, it would just be very computational. Your best bet would just to use matrices in the form Ax=b where A is your coefficients, x is a vector of your variables [(w,x,y,z) for 4 variables] and b is a vector of your intercepts. Then just do x = A^-1*b to solve. He does this in earlier videos for a two by two matrix.
when you are solving this equations.are you thinking about special case in your mind?
u are the best
Mr Khan: "My wife is downstairs, im supposed to go eat out".
...Interesting
Definitely more confusing than any other video I've seen from them.
2019?
Nah 2021 lol😆
Did he mention the triangular form before he mention the matrix?
@pentakillace You're obviously not in university. This is also used in first year linear algebra. It's used for solving matrices and what not.
what is the program he use it?
Hats off to you !!
I would suggest to viewers to try to watch it without sound. You can learn more that way I think
Thank you my savior