Question

If the Integral of 1/(1+x^2) dx = tan^-1(x) + C...
Then, the Integral of 1/(a^2+x^2) dx = ???

Choices:
a) tan^-1(x/a) + C
b) (1/a)[tan^-1(x/a) + C
c) tan(x) + C
d) cot^-1(x/a) +C

Anyone? Thanks!

Answer 1

And can you please show me why? Thanks!