1. The problem statement, all variables and given/known data integral of (1+e^x)/(1-e^x) dx 2. Relevant equations 3. The attempt at a solution The TA said to make u = e^x So, du = e^x dx. dx = du/e^x. Since e^x = u The integral now is (1+u)/(1-u)u I am confused as to what to do after distribute the u in the bottom.