What is the derivative of f(x)=x⋅cosxf(x) = x \cdot \cos xf(x)=x⋅cosx?
cosx−xsinx\cos x - x\sin xcosx−xsinx
sinx+xcosx\sin x + x\cos xsinx+xcosx
−xsinx-x\sin x−xsinx
cosx+xsinx\cos x + x\sin xcosx+xsinx