If $u=\log\begin{pmatrix}\large\frac{x^{2}+y^{2}}{xy}\end{pmatrix}$ then $x\large\frac{\partial u}{\partial x}+$$y\large\frac{\partial u}{\partial y}$ is

Question

$$\begin{array}{1 1}(1)0&(2)u\\(3)2u&(4)u^{-1}\end{array}$$