Find the anti derivative for 4/(x^2+1)

3 answers

4 (x^2 + 1)^-1

4 * -1 * (x^2 + 1)^-2 * 2x

-8x / (x^2+1)^2
Your question is of this type:

Integral of du / (a^2 + u^2) = (1/a) tan-1(u/a) +c
OOPS... missed the "anti" part

that is the derivative