Product rule generally seems straight forward but what if one comes across a scenario involving 3 functions instead of 2? For example: d/dx[x*e^(x^2)*f(x)] f(x) is just some generic function So there three functions of x are: -x - e^(x^2) -f(x) I am personally lost about how to solve this problem. I was considering doing product rule on the first 2 functions and then using that to do another product rule by involving the third function. If only f(x) was known than this problem could be much more predictable. If anyone can help steer me in the right direction I would greatly appreciate it. Hopefully this problem isn't more simple than I thought.