Calculating a Limt By Factoring and Canceling

[chickmitten]

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[patrickJMT]

@chickmitten : )

[Teshlakh]

can i use l'hopital's rule it's easier?

[orionbassmaster666]

god Patrick your a life savior , thanks for the videos and hard work , your simple approach simplifies alot of doubts , god bless buddy ^^

[patrickJMT]

@orionbassmaster666 happy to help : )

[razerbeem]

How would you factorize it if there is an x after the 4?

So if it is... x^2 - 4x

? I have a test tomorrow, I would really appreciate the help please :)

[warnexus]

great stuff! this video helped me refresh my memory!

[psp785]

do u have a video for solving limits using tables

[audioash]

instead of having teachers lecture we should cut the bs and just have mass viewings of these videos.

[heyyy3210]

PLEASE continue making these videos! For all the rest of the concepts of Calculus!

[patrickJMT]

@heyyy3210 tons of calc stuff out there by me : )

[nanone1994]

Just started Calc first semester for my senior year and I am doing really gooooooood ;) yaaay love maths !

[turistjohn]

Just started Calc first semester bearly on chapter 2... I'm using your videos all semester :)

[jojogirl2008]

THANKS SO MUCH! i appreciate ur videos so much!

[patrickJMT]

@jojogirl2008 you are very welcome ; )

[zoecastillo717]

What would I do without you?!!!!!

[patrickJMT]

@zoecastillo717 weep softly :  )

[benlaw227]

nice video. it really helped me out a lot.

[TheHypaLink]

Outstanding.

[doorfridgemagnet]

@patrickJMT The audio is now out of sync its all fuzzy

[wondy17]

You don't understand the level of thanks i'm at right now, honestly, i was struggling so much with limits, just looking at a limit i was confused, but this video really helped man, thanks a lot, and i like how you teach, too, it's so easy to follow along, keep it up man

[bhoskaronkar]

thanx



[djwarped14]

i love you patrick

-djwarped from philippines

[91HPS]

If I wasn't such a broke student I would happily donate, I know you don't do this for money, but because you enjoy helping other people. Just wanted to say thanks so much for taking the time to help myself and other students with our calculus, really do appreciate what you do and it helps me actually understand calc. Keep it up!

[stockingzxo]

Love these. My Calc teacher sucks. I now understand :) THANKS !

[hockeygrl195]

I should be paying you.... not my calculus teacher.

[Abdallah0822]

God bless you a million for all your videos

[dwigzo15]

God bless u

[EhancedTrance]

do you have a donation link?

I WILL gladly pay you.

[patrickJMT]

@EhancedTrance there used to be one on my old website: justmathtutoring dott com

[NtS5555]

Thanks a lot! Doing midterm studying and my notes didn't have any examples for indeterminate limits. It took me about 30 seconds of watching your video for me to figure it out.

[Kingpin745]

Dude why don't they have more instructors like you.. I frigging hate my professor wid a passion!!!

[TexaninSpain]

great job.. I´ll be telling eveyone from QUMT class about you!!! Thanks for the help...

[fjeezy03]

really..this has been beyond helpful..i had no clue about limits now I feel like i can teach people haha, but really thanks, you should become a professor

[erinnikole11]

These videos are beyond helpful! Thank you so much! My calculus teacher told me about you, and she commonly refers to you as "Math God"!

[erinnikole11]

These videos are beyond helpful! Thank you so much! My calculus teacher told me about you, and she commonly refers to you as "Math God"!

[MizzFlyy]

im taking math right now and the last time i took math was 2 years ago!

i forgot everything and this video was really helpful!

thanks so much!

[lolita123lit]

thank you so much :)

[deathdealer13cat]

dude u must be the best teacher ever. u should get money for this. are u a youtube partner

[patrickJMT]

@deathdealer13cat i am now a partner yes, so i get a little bit from the videos!

[skyfaze]

@patrickJMT Congratulations!

[vividmonkey]

@patrickJMT dude. awesome. you save my life distance learning life!

[katiemartin220]

I have watched several videos now by a variety of people. None have compared to this guy! Some are good, but don't break down the problems as well as patrickjmt. Thanks for the help!!!!

I was beginning to freak out because of my class and "not-so-great" teacher.

[patrickJMT]

@katiemartin220 glad you like the videos! : )

[balasing25]

your so genius and kind..you know that there a lot of people that cannot understand easily the math,but you explain it in a very simplest way so that other can understand it..i already watch some tutorial videos but your videos show some humbleness not like other videos..the mentor carrying their knowledge but not knowing that the listener needs simple explanation to understand...

[jayronsoares]

I would like to buy the core of calculus videos, because I will start calculus in statistician course degree, please can you help me with this?

[patrickJMT]

@jayronsoares i do not have dvds at the moment, but everyone keeps asking, so i may burn them off at some point. some videos are available for download via youtube for a fee

[Greeneyehawk13]

this is great! Thank you! This is going to help me with my test in a few weeks

[fhk55]

thnx alot

[nevabagdown]

why do you do (x -2)(x+2) for x-4

[Noremae]

@nevabagdown bcoz it is the factor of x2-4, and if you don't you'll get 0/0. and the limit does not exist

[squisheebananas]

I wish I could hug you.

[abuokab]

I wish I watched this a month ago. I will see all of your videos. Thanks a lot

[OniLink10]

So wait, we just factor the equation to cancel out the bottom? Makes sense.

[wikkk16]

Great!

[karlkarlkarl1234]

I'm not sure how people find limit hard, it is really simple.

[Noremae]

@karlkarlkarl1234 i think bcoz they have to factor or conjugate.

[dhanedhar]

that means limit of a function at x=a is a point y=b for point x=a which is not defined for the function whose limit we are taking at x=a

[acousticky14]

i love you!

[FcLS1Rx7]

Can't you just take the derivative of the numerator and the denominator? I believe its the same thing no factoring involved.

[14jlim]

i dont think you can, thats the l'hopital rule, which must be 0/0

[14jlim]

and my mistake lol it is 0/0, yea you could use lhopitale rule

[TusksRUs]

You could, but this is a video explaining how to do limits generally - rather than specific cases (L'Hôpital's rule is only valid for when the limit gives 0/0 or infinity/infinity).

But to answer your question, you could, in this case, the answer would still be 4.

[DiordnaDionaraP]

If the two thing do not describe the same functio. Why do we use an equal sign?

i mean, if the graph is diferent then the two ecuations must be different.

[tenshimessence]

The equations are not equal, but the limits of the two equations are equal.

Both equations approach the same value when x approaches 2, so you can say that the limits are equal.

Does that make sense?

[accarl]

thanks a lot it really help me understand!!

[xzKyouzx]

Could you help me with this question?

lim [(x^n)-1] / (x-1)]

x->1

The answer is n. I can't figure it out help please =)

[ruchieru]

Factor [(x^n)-1] so that it equals to:

(x-1)(1+x^2+x^3+x^4+...+X^(n-1­))

And since you have a (x-1) in the denominator as well you can cancel those two out. So you're left with the whole (1+x^2+x^3+x^4+...+x^(n-1)) term. And since x approaches 1, and whatever power of 1 is always equal to 1, then the sum of all those 1's to right to the end where you have x^(n-1) would just be n, since you also have a 1 at the beginning. So in essence it's really 1+n-1, which is n.

[xzKyouzx]

Thank you very much!

[DiordnaDionaraP]

I can do it but you'd need to know how to derive. the method is called L'hopital and he has videos of it in his page.

[drgirlfri3nd]

Ohhhhh thank you thank you thank you. And thank you.

[sumacc87suncco]

L=(x-2)(x+2)/(x-2)=4

[sfking00]

Dude i love you as much as one man can love another man without being gay. thanks

[DrSplicer]

THANK YOU!!......again haha, your videos are very help full, and the best thing is you can rewind haha

[patrickJMT]

yes being able to rewind is very useful :)

[trueteen]

THANK YOU ! you make my life so much easier

[dahhlingLCx24]

@DrSplicer lol i know. i just realized that today aswell :P

[aparrotslife]

I appreciate you posting this video, Patrick! It is very helpul! :)

[patrickJMT]

glad it helps : )

[xXinvalidentryXx]

im taking AP calc next year & i've been working on this summer assignment that i'd have no clue how to finish without your videos, since it's summer and all. Thank you VERY much, i'll definitely use your site for future reference.

[ssk360]

ur vids are great,

[kdwaechter]

So....limits are just a way of defining a point that is normally undefined?

[jaimeastorga2000]

NO.

Intuitively, limits are the value that the output approaches as the input approaches something else. The removable discontinuity in the graph at x = 2 is a place where the graph is undefined. However, it is easy to see that, as x -> 2 ("x approaches 2") from either side, the y value approaches 4. Ergo, 4 is the limit of the function as x -> 2. This is true regardless of whether there is a missing point (removable discontinuity) there or not.

[patrickJMT]

jaimeastorga2000 is 100% correct

[MrEthioTeddy]

Thank you very much, you make math so simple.

[cubencis]

why don't they teach L'Hopital from the get go i wonder... thanks for the review

[patrickJMT]

cause you have to learn limits before you can talk about derivatives, and derivatives are required to use L'H!

[matrixfull]

I've searched many sites and looked in many books...but they all want explain in such scientistic way that it totaly confuse me. This video is soo much more simple. This will really help me a lot in my homework. Thanks!

[v13dinei]

thank you for this video.

this is excelent for my study... I am from Brazil.

[ViadoMundo]

Nice one! (I'm watching a lot of your videos in your webpage)

[furin121]

Thank God for you. :) I'm having such a hard time in calc because I didn't get a good grasp on doing limits (I thought they were harder than they actually are). I've watched about 20 of your vids so far on various items and can say my anxiety when facing my math homework has gone down tremendously. Please keep providing this information to me and others like me!

[patrickJMT]

no problem! i have lots of videos posted, and do not plan on removing them any time soon. : )

so all one needs to do is just look!!! : )

[pookiehohn]

These videos are so helpful!

[patrickJMT]

wonderful! you can now download them and take them with you! : )

[pookiehohn]

I really would like to, but I have no money!!! : (

[patrickJMT]

ok keep watching for free!! : )

[magic100172]

thanks heaps man.. ur fucking god