Hi. I have a problem with a question. Basically, I have an integral that goes from x=0 to x=1, and I'm supposed to make a change of variables like this: Let x = 1 - y^2. The problem I'm having is trying to find the limits of integration after the change of variables. Since y = +/- (x-1)^1/2, I have y = -1 or +1 for the lower limit. Am I supposed to just use either one? I'm so confused.