- #1
Supernova123
- 12
- 0
I was wondering if there is a convenient way of checking if a substitution is correct or not.
For example, I tried solving for ∫(1/(a^2-x^2)dx using two different substitutions, x=acosu and x=asinu giving different solutions. I got the integral as arcsin(x/a) using x=asinu and -arccos(x/a) using x=acosu. But which one of these is the correct one and how do I tackle this sort of problem if it arises again?
For example, I tried solving for ∫(1/(a^2-x^2)dx using two different substitutions, x=acosu and x=asinu giving different solutions. I got the integral as arcsin(x/a) using x=asinu and -arccos(x/a) using x=acosu. But which one of these is the correct one and how do I tackle this sort of problem if it arises again?