The table below gives the values of \( f(x) \) at five equidistant points of \( x \):
Then the approximate value of \( \int_0^2 f(x) \, dx \) by Trapezoidal Rule is:
If \(u = \sin^{-1}\left(\frac{x}{y}\right) + \tan^{-1}\left(\frac{y}{x}\right)\), then the value of \( x \frac{\partial u}{\partial x} + y \frac{\partial u}{\partial y} \) is: