Differential Equations

Let y = y(x) be the solution of the differential equation \(x\tan \left( {{y \over x}} \right)dy = \left( {y\tan \left( {{y \over x}} \right) - x} \right)dx\), \(- 1 \le x \le 1\), \(y\left( {{1 \over 2}} \right) = {\pi \over 6}\). Then the area of the region bounded by the curves x = 0, \(x = {1 \over {\sqrt 2 }}\) and y = y(x) in the upper half plane is :