# Do I have to use By Parts?

• Mar 4th 2010, 05:02 AM
NFZ17
Do I have to use By Parts?
$\int x^2(1+x^2)^2dx$

Do I have to use by parts here or can I expand the brackets and get:

$x^8/8+2x^6/6+x^4/4+c$

• Mar 4th 2010, 05:24 AM
Quote:

Originally Posted by NFZ17
$\int x^2(1+x^2)^2dx$

Do I have to use by parts here or can I expand the brackets and get:

$x^8/8+2x^6/6+x^4/4+c$

Simplest is to expand the brackets, but you should then have

$\int{\left(x^2+2x^4+x^6\right)}dx$
• Mar 4th 2010, 05:59 AM
NFZ17
Thanks,

I came up with

$x^7/7+2x^5/5+x^3/3+c$

$\int x^3 (1+x^2 )^2 dx$
$\int x^2 (1+x^2 )^2 dx$