# Calc 2 Help, several problems!

• Jan 1st 2011, 04:28 AM
Spoolx
Calc 2 Help, several problems!
So I am stuck on several problems, I assume they are all solved the same way or roughly the same way but I dont know where to go.
I am pretty good with my integration, and even basic integration by parts, but this stuff has me stumped.

Any help is greatly appreciated.

Thanks

I know for the most part they are all integration by parts, just not sure what parts to choose.

1) ∫(e^1/x)/x^2

2) ∫x^4lnx

3) ∫x^2e^x^3

4) ∫1/x(lnx)^3

5) ∫x^3e^x^2/(X^2+1)^2

6) ∫ln2x/x^2

7) ∫e^2xsinx

I know its alot, but any help is greatly appreciated.
Classes start next week and I am trying to freshen up my skills.
• Jan 1st 2011, 04:37 AM
mr fantastic
Quote:

Originally Posted by Spoolx
So I am stuck on several problems, I assume they are all solved the same way or roughly the same way but I dont know where to go.
I am pretty good with my integration, and even basic integration by parts, but this stuff has me stumped.

Any help is greatly appreciated.

Thanks

I know for the most part they are all integration by parts, just not sure what parts to choose.

1) ∫(e^1/x)/x^2

2) ∫x^4lnx

3) ∫x^2e^x^3

4) ∫1/x(lnx)^3

5) ∫x^3e^x^2/(X^2+1)^2

6) ∫ln2x/x^2

7) ∫e^2xsinx

I know its alot, but any help is greatly appreciated.
Classes start next week and I am trying to freshen up my skills.

Please don't post more than two questions in a thread. Otherwise the thread can get convoluted and difficult to follow. See rule #8: http://www.mathhelpforum.com/math-he...ng-151418.html.

Also, please show some effort. You must have some ideas .... Post what you can do or have tried and make it clear where you get stuck.

I will answer the first by saying that you make the substitution u = 1/x. In fact, several of them are done using the method commonly called u-substitution. I suggest you review class notes or textbook. Ideally, when/if you re-post in the way advised in the above link, you will at least group them in threads according to what you think will be the required technique.