Integration by Parts Example 3

[mmogib]

Great Job! I'm your biggest fan.

I have a comment though. The differential of u, du, is equal to the differential of x, dx, ie. du=dx, and dv=sin(x) dx .

[mage1413]

my entire reading week calc studying consisted if watching your videos :) more useful than studying my notes. keep up the great work :)

[TheIntegralCALC]

@mage1413 So glad you found them useful! :)

[Agreedtodisagree]

this is gonna end at a pornographic website.

[crane550]

Will you marry me?

[Taylaron1]

Smart and beautiful! Good thing you had a sweatshirt on or I wouldn't be paying attention to the math! Your beautiful face was almost too much for my attention span. Well done!

btw, dx is on the end because the integral of x is technically 1*dx.

[USPtube1]

I'd hit that.

[paintcrazed]

it helps when there's a cute girl teaching me how to do math :)

[sierratwo1]

Hi, can i ask if there's a method to determine 'u'?

I was taught today in lecture this:

Logarithmic

Inverse Trigonometric

Algebraic

Trigonometric

Exponential

It's like using this set of words (in order) to determine the 'u' for instance in xln(x). The ln(x) appears before the algebraic (x) and then we take 'u' as ln(x) instead.

I'd just love to know if this really works for all the integration by parts problems.

[TheIntegralCALC]

@sierratwo1 It works for almost all u-substitution problems, but there are a few rare instances where it won't work perfectly. Definitely use it as a guide though! :)

[magicguy1988]

Technically speaking, the du should be du=dx and dv should be dv=sin(x)dx. Because du and dv are differentials, not simply a derivative.

[a7ab2aa7a3]

trust me without ur videos i was to fail in more than 8 math 3/4 exams ^^ u r so damn awesome :$ and sexy :P :P :P

[TheIntegralCALC]

@a7ab2aa7a3 Thanks!! :D I'm so glad the videos are helping!! :D

[pb550]

well done, mate, well done!

[TheIntegralCALC]

@pb550 Thanks! :)

[bakopala]

Hey thanks a lot for your lessons.Your lessons helped me pass maths and eventually obtain my science degree.Maths has always been a challenge to me ,but thanks to your videos i finally cracked it on my second atttemp(Retake).A big thumbs up to you and Patrick.Cheers !!!

[TheIntegralCALC]

@bakopala Oh awesome!!! Good for you, and congratulations on your science degree!! :D

[bakopala]

@TheIntegralCALC Thanks !!

[maccamracecar]

Thank you very much! I've never seen that formula before but it's nice to know 2 days before your final. ^^

[rolle16]

Thank you, your video's are awesome :) i hope they will help with my exam in two days. I do ,however, have a question. If you have the integration for Sin(ln x)dx, can i use the ln x ? Ive just spent over 30 min in a futile attempt to find the solution for this one. Will you help me with this one?

[tjpoulose03]

You saved my education

[TheIntegralCALC]

@tjpoulose03 Awwwww! That's awesome!! Thank you so much for letting me know that the videos have been helpful!! :)

[Saintdeken]

....

[FreshSqueezedJuice1]

I can not even begin to describe how much your videos helped me out. Thanks!

[TheIntegralCALC]

@FreshSqueezedJuice1 Awww, you're welcome! It means so much to me knowing the videos are helping, even in the slightest way.

[DrummerRF]

@FreshSqueezedJuice1 Mostly help you out because you now know there are beautiful girls that actually like Calculus. NO MORE FOREVER ALONE ENGINEERS!!

[cunje01]

@DrummerRF lol

[ZedDotNein]

Not a problem. Like I said, it's picky because for most calculus students it is just notation. But, as you pointed out, down the road, especially for people going for math, physics, engineering degrees, it's a costly thing to leave out.

[ZedDotNein]

It's picky, but when you assign u=x, the derivative of u=x is du = dx (which isn't trivial, and not just notation). Also, when you assign dv it should be dv = sin x dx.

When you do this and you are plugging all of your assignments back into the Parts formula you won't be missing anything and your next step will be more clear.

Keep up the good work, btw. It makes me happy to see that there are good instructional videos on calculus out there!

[TheIntegralCALC]

@ZedDotNein You're totally right. I always tried to leave it out to make it simpler for people, but I don't want to confuse anyone down the road, so I've moved away from leaving it out, and make sure to include it now. Thanks so much for your support! I appreciate it! :D

[superandy456]

@ZedDotNein Thanks for pointing that out cause that really confused me when she said that dx is just notatition

[CrackHeadForLife420]

The "dx" is not just notation. Just wait and see! ;)

Look up Riemann-Stieltjes integration to get a peek.

[norabelanger]

SO much better than my prof..

[TheIntegralCALC]

@norabelanger Thanks! :)

[24sbm120]

You are a beautiful nerd! :)

[ToriTeee]

thank you, this helped a ton, you explained it to a dummy like me :)

[TheIntegralCALC]

@ToriTeee I'm glad it helped, and I'm sure you're not a dummy!! :D

[ThePakChina]

Thanks sister

[TheIntegralCALC]

@ThePakChina You're welcome!! :)

[integralmath]

Those 'terms' of which you speak, u and dv, aren't terms; they're factors. Otherwise, an acceptable explanation.

[kaityplusmichael]

the constant "C" is added at the end because this is an indefinite integral. very helpful though :) great job

[vinoth929]

really nicely done, you even say the most basic things, which most professor dont mention may be caz its boring for them or he thinks others know it,but u make everyone to understand who dont even the basics,thanks a lot, and i am confident now

[TheIntegralCALC]

@vinoth929 People say algebra is sometimes the hardest part of calculus, so I never want to skip anything! Glad it helps, and even more glad that you're feeling confident! :D

[fahdkhanyousafzai]

thanks, no really, your video helped a lot. god bless you.

[TheIntegralCALC]

@fahdkhanyousafzai Thank you, I'm so glad! :)

[adphinn1]

great video.



[TheIntegralCALC]

@adphinn1 Thanks! Glad you like it :)

[richardedward123]

Very clear and unpretentious. Good teaching skills. I’m training for the fundamentals of engineering exam after graduating some 16 years ago so I’m re-learning everything I’ve forgotten, which is pretty much everything. This really helps! Thanks!

[TheIntegralCALC]

@richardedward123 Thank you so much! And good for you for getting back to school after so many years. Best of luck to your on your exam!! :D

[squeakins]

Thank you for making this video needed Calc refreshers for my P-Chem class AHHH!!! Thanks again !!.

Ps Cute & smart dang!!

[TheIntegralCALC]

@squeakins Awww! You're welcome, glad it helped!! :D

[squeakins]

@TheIntegralCALC Umm what if i have a problem i need help on could I ask ??

[TheIntegralCALC]

@squeakins Sure! :) I started a site that's just for calc question and answer, which makes it a little easier for me to get back to people. If you want to ask a question, could you please post it on mycalculushelp (dot) com? I'll do my best to answer if I can!! :D

[xeon980]

This video is brilliant!! I have my year 12 maths exam coming up, and I had forgotten some integration. Once I saw this video, I am all good with it now! - Very helpful video!!:)

[TheIntegralCALC]

@xeon980 Awesome! I'm glad the video helped, and GOOD LUCK to you with your exam!! :D

[xeon980]

@TheIntegralCALC I ended up getting 96% for my exam! Most of it was integration which I was happy with, especially after watching these videos! Once again, I thank you heaps! :D

[TheIntegralCALC]

@xeon980 WOW!! That's awesome, congratulations, and thanks for letting me know!! :D

[rachellee85]

I loooveee you!! You saved my course really. Greetings from Sweden!!!

[TheIntegralCALC]

@rachellee85 Awwww, I love you too!!! Thank you so much for letting me know that the videos have helped, It really makes me feel good! :) Congratulations on your success, keep it up, and don't hesitate to let me know if there's anything I can do for you in the future. :D

[rbeekawoo1]

U r cute! Meeeeow!

[thomasking55]

Great. Dyslexic friendly :)

[mteferra22]

Last second help before my final? I think so! Thanks this makes much more sense now.

[TheIntegralCALC]

@mteferra22 I really hope I helped! Did you rock the test?! :)

[Kushmilano]

I am happy for the fact that people like her make math more interesting in general to understand. Young people are energetic in their voice which surely attracts other in my opinion. Thanks for your videos! you helped me a lot. Cheers from India !

[arondeos]

no entendi muxo XD pero la maestra esta biutiful!!!! <3

[pedjasta]

dv can't be only sinx but dv = sinx dx :)

[TheIntegralCALC]

@pedjasta True! :) I think leaving it out at that step makes this problem a little easier to understand for a lot of people, and you can add it back in after plugging u, du, v and dv back into the formula, especially since it's not something that effects the outcome of the problem. :) Thanks! :)

[akmed16]

thank you that was helpful

[TheIntegralCALC]

@akmed16 You're welcome! :)

[ricanhurdler]

i thought sinx=cosx and cosx=(-sinx)??

[TheIntegralCALC]

@ricanhurdler That's true if you're talking about derivatives... The derivative of sinx is cosx and the derivative of cosx is -sinx. But in this example, I'm talking about integrals. The integral of sinx is -cosx and the integral of cosx is sinx. Hope that helps! :)

[pellieasaurus]

i like your signature touch on these subjects! Come to Louisiana and teach! PLEASEEE!!!

[TheIntegralCALC]

i'm working on the shorter part... :) and fewer "ums" too! :)

[medo1555]

thanx ,,,, it was great

plz make it shorter next time

and hey u look soooo cute ^_^

[OdCzapyZestaw]

damn, thanks ! ;D