TeX source:
\begin{array}{lclcrcl}\quad\mathbb{D}&=&\mathbb{R} \cr \cr f(x) &=& (x^2+1)\sin(x) \cr \cr \quad u(x) &=& x^2+1 & \Rightarrow & u'(x) &=& 2x \cr \quad v(x) &=& \sin(x) & \Rightarrow & v'(x) &=& \cos(x) \cr \cr f'(x) &=& 2x\sin(x)+(x^2+1)\cos(x) \end{array}