Thank you very much. This video is helping me a lot, as I am currently doing summer homework to prepare for my AP calculus class, and I have to teach myself. Very helpful video!
youtube is such a sad place sometimes. imagine how many millions of people this channel has helped, yet it only has 191k subs :( and this video is from 2013... oh well, this video helped me a lot, thank you!
@@pearlemmaribatulan7808 hes not changing the sign or adding and subtracting anything. hes simply taking 3 common from both 3 and 3x. if you open the brackets. you will get 3+3x again. the original value.
is there a more rigorous way of finding a one-sided limit? Like what if I am trying to use it to do the first derivative test for testing a function's extrema, I do not know whether the limit at c-0.1 and c-0.01 has the same sign. tl;dr: is there a way to find the one-sided limit given the delta from the target value is arbitrarily small?
I still don't understand why you wanted to use 4.1? Why cannot solve the question directly from the question? Why need to guess the x value? If don't guess, can I get my answer directly?
I think the question was how do you solve for that -1 value algebraicaly. In the video you showed how figure it out by testing and approximate number, but I would also like to know how to solve for that value by manipulating the expression. thanks.
If x+4 inside the absolute value is positive, x+4/x+4=1. If x+4 inside the absolute value is negative, -x-4/x+4=-1. Since x is approaching the limit by the left side of -4, the number should be smaller than -4. Algebraicaly, using another number like -4.01, (-4.01+4)/(-4.01+4)=.01/.01, so the answer would still be the same, which is -1.
-4.1 was only used to inspect the occurrence of the term | x + 4|/(x+4) as x approaches -4. After that, you can once again inspect the (x + 7) part of the term as x approaches -4. Essentially he just used a limit law, so for both terms he was always approaching -4 from the left.
For the last problem, why the guy choose the value of x as x approaches -4+? He is approaching it from the right? Shouldn’t it be he used 3.9 rather than 4.1?
first x aint approaching nothing x is the coordinated line of the spectra is aline that croses the equator n the y is another line that never moves,xn y are letters giving to this spectra. now u have x-->3 x approaching 3 from the equation ,(approaching even if it dont move its o ready approaching), see this is where all the math is wrong u guys are theorizing cus like i said x dont move we plug numbers points variables etc etc on th x line ,bu never moves,u should said the variables pluged at x line would converge at certain variables of y line,now on the physics world we move the equator line aka x intersection or the poles lines n/s of y ,and axialy we dont move it at all, we just cut the fuckers at some point.we never move the damn lines at all.
As a student of 1 year maths after a couple of hours spend on thinking how to simplify similar limit I must tell you that you saved my life :)
Thank you very much. This video is helping me a lot, as I am currently doing summer homework to prepare for my AP calculus class, and I have to teach myself. Very helpful video!
youtube is such a sad place sometimes. imagine how many millions of people this channel has helped, yet it only has 191k subs :( and this video is from 2013... oh well, this video helped me a lot, thank you!
it sounds like there is a party near by. idk
Omgg thank you! I got a differentiate/limit test tomorrow, I’m studying to become a math teacher and your videos really help me!!!
How did you get (1-x) in 3x? How it become 0? @ 4:36 and also how did you get the number -4.1? Is it random number? @ 8:03
Thanks for the vid although I don't get where you got the 3(1-x) in the second example.
Where's the 3 - 3(1+x) ?
@@pearlemmaribatulan7808 hes not changing the sign or adding and subtracting anything. hes simply taking 3 common from both 3 and 3x. if you open the brackets. you will get 3+3x again. the original value.
i thought that limits involving absolute value had to be split up. [(x+4) if x>or=to 1] and [-(x+4) if x
I'm 3 years late but maybe this will help for future viewers:
Since x is approaching -4 from the left side, it means x
is there a more rigorous way of finding a one-sided limit? Like what if I am trying to use it to do the first derivative test for testing a function's extrema, I do not know whether the limit at c-0.1 and c-0.01 has the same sign.
tl;dr: is there a way to find the one-sided limit given the delta from the target value is arbitrarily small?
thanks man you're a big help
Thank you!! This video was a BIG help!!
How do you know that the function is with tangent slope of one?
you're the best teacher. thanks a lot.
The first one is + infinity right?
I still don't understand why you wanted to use 4.1? Why cannot solve the question directly from the question? Why need to guess the x value? If don't guess, can I get my answer directly?
I think the question was how do you solve for that -1 value algebraicaly. In the video you showed how figure it out by testing and approximate number, but I would also like to know how to solve for that value by manipulating the expression. thanks.
If x+4 inside the absolute value is positive, x+4/x+4=1.
If x+4 inside the absolute value is negative, -x-4/x+4=-1.
Since x is approaching the limit by the left side of -4, the number should be smaller than -4.
Algebraicaly, using another number like -4.01, (-4.01+4)/(-4.01+4)=.01/.01, so the answer would still be the same, which is -1.
So that's how you make a damn bracket. Holy shit.
I don't why, but this cracked me up. X^D
Thank you
Thanks for this.
I have an examination in Basic Calculus 2 hours away from now. :/
I hope it turned out great! :^D
@@MySecretMathTutor it did! Thanks to this video!
Can you square the modulus?
why are you using two different x's at 7:47 ? (-4.1 and -4) I thought that the same x was used for both sides of the equation
-4.1 was only used to inspect the occurrence of the term | x + 4|/(x+4) as x approaches -4. After that, you can once again inspect the (x + 7) part of the term as x approaches -4. Essentially he just used a limit law, so for both terms he was always approaching -4 from the left.
Thank you sir🤩
Thank you sir
For the last problem, why the guy choose the value of x as x approaches -4+? He is approaching it from the right? Shouldn’t it be he used 3.9 rather than 4.1?
Yeah but it wouldn't matter, any negative number would still equal -1
In the second problem you have calculated left hand limit but really ght hand limit doesn't exist so that the whole limit doesn't exist?
Correct, for a general limit to exist, it must exist from the right and left hand side, and these values must agree.
thank you really very much helped me alot......
where did the nine go? how did we get (x+3)(x-3)
@@mrs.carleshabutler6823 go back to basic algebra and factoring perfect squares lol
thanks man
THANK YOU!
Thank you!!
where did the nine go? how did we get (x+3)(x-3)
Look up how to factor perfect squares.
To succeed in this you should probably know how to factor polynomials.
thanks
shouldnt it be .1 why 1?
Any number divided by its self is 1. 1/1=1; 5/5=1; so .1/.1=1 is no different. It just might look weird because it's a decimal.
|-4.1+4|/-4.1+4 i not under stand please someone help me
hello
best
first x aint approaching nothing x is the coordinated line of the spectra
is aline that croses the equator n the y is another line that never moves,xn y are letters giving to this spectra. now u have x-->3 x approaching 3 from the equation ,(approaching even if it dont move its o ready approaching), see this is where all the math is wrong u guys are theorizing cus like i said x dont move we plug numbers points variables etc etc on th x line ,bu never moves,u should said the variables pluged at x line would converge at certain variables of y line,now on the physics world we move the equator line aka x intersection or the poles lines n/s of y ,and axialy we dont move it at all, we just cut the fuckers at some point.we never move the damn lines at all.
thanks