# Math Help - Derivative of an integral

1. ## Derivative of an integral

Differentiate: $f(x) = \int_{0}^{x} \frac {x}{1 + t^2 + sin^2t}dt$

I am not sure how to do this, since there are 2 different variables in the integral (x and t).

2. Take the x out of the integral (assuming it doesn't depend on t, which it doesn't look like it). Then use the product rule on x and the integral.