I think I'm getting the hang of evaluating integrals, but I just wanted to check my answer. Is someone able to confirm if this working and result are correct?
Substituting values gives:
1. Change the integral terminals and then evaluate the new definite integral: , or
2. Get the anti-derivative in terms of the new variable, re-substitute to get the anti-derivative in terms of the old variable and then evaluate the definite integral in terms of the old variable: .
You do one or the other. You're mixing both together.
The correct answer is 1/2: