Hey, I have to find the $\displaystyle f^{(n)}(x)$ of function $\displaystyle f(x) = x \cdot \cos(2x)$. I know I need to find a Leibnitz formula for derivative of product, but how?

Also, I have to solve this formula explicitly, so, $\displaystyle f^{(n)}(x) = ...$.

Please help