1. The problem statement, all variables and given/known data ∫(ex)/(2ex+2)dx 2. Relevant equations and im told to use: u=2ex+2 3. The attempt at a solution If i use u=2ex+2 as the task says; du/dx = 2ex and dx =du/2ex ∫(ex)/(u)du/2ex=∫(1)/(2u)du=1/2ln|u| + c =1/2ln|2ex+2| according to the book the answer should be 1/2ln|ex+1| however if i use u =ex+1 and write the integral 1/2∫(ex)/(ex+1)dx i get the correct answer. Where am i going wrong?