I can't seem to get the correct answer for this:

Find the indefinite integral by using the substitutionx= tan(http://www.webassign.net/images/theta.gif).

integral x^2/(1+x^2)^2 dx

Thanks

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- October 15th 2008, 05:10 AMG-manPlease solve this calc. trig substitute question
I can't seem to get the correct answer for this:

Find the indefinite integral by using the substitution*x*= tan(http://www.webassign.net/images/theta.gif).

integral x^2/(1+x^2)^2 dx

Thanks - October 15th 2008, 06:28 AMvincisonfireReply
tan(t) = x

sec(t)^2 dt = dx

tan(t)^2 * sec(t)^2 dt/(1+tan(t)^2)^2

tan(t)^2 * sec(t)^2 dt/(sec(t)^2)^2

tan(t)^2 dt /sec(t)^2

sin(t)^2 dt

Integrate this using trigo identities on wikipedia.