1. The problem statement, all variables and given/known data Using Leibniz's rule to find dy/dx for y = integral of e^-t from interval: [ln(x) to ln(x+1)] 2. Relevant equations 3. The attempt at a solution dy/dx = e^-(ln(x+1))*(1/(1+x))-e^-(ln(x))*(1/x) = (x+1)/(1+x) - (x/x) = 0 Im not sure what I'm doing wrong or how to properly use leibniz's rule... i checked wolfram alpha and my answer doesn't look right. also side question, my teacher manages to simplify integral of (x^2)/(x^2+a^2)^2 to (integral 1/(x^2+a^2) - a^2*integral(1/(x^2+a^2)^2) if you have a clue on how he reaches to that conclusion i would appreciate it.