Calc integration prob, need help desperately!!!

[kaiotes]

can someone tell me if i did this correctly?
integration problem
i got exam tomororw kind of confused right now!

this is the property
S 1/(1+x^2) dx = tan^ (- 1) x + C


S x / (1+x^4) dx
so i let u = x^2
du = 2x dx
1/2 du = x dx

1/2 S du / 1+ u^2
1/2 tan^ (-1) U +c
1/2 tan^ (-1) x^2 +c
is this righT???/

 

[Napalm381]

Looks OK to me

Remember, you can always check an integral by just taking the derivative of your answer. Don't forget the chain rule!

 

[thraashman]

yes it's right, or at least my TI-89 says it is.

 

[kaiotes]

thanks a lot palm and thrash
btw, this prob has X on top, it is right? i somehow still have doubts

 

[bobtist]

The x on top goes away with your 2xdx->du. Looks good.

 

[bobtist]

Thraashman, you and TI-89!!




I want one.....

 

[Viper GTS]

<-- Has a 92+... That he hasn't used in a year and a half.



Viper GTS

 

[kaiotes]

alrighty then.
thanks for all of your help!!!