Derivatives

Given the function

   f(x,y)=5x^3+x^2cosy 

compute:
    \frac{\partial{f(x,y)}}{\partial{x}} , \frac{\partial{f(x,y)}}{\partial{y}} , \frac{\partial^2{f(x,y)}}{\partial{x}^2}\frac{\partial^2{f(x,y)}}{\partial{y}^2}
   
and show that    \frac{\partial}{\partial{y}}\frac{\partial{f(x,y)}}{\partial{x}}-\frac{\partial}{\partial{x}}\frac{\partial{f(x,y)}}{\partial{y}}=0