Question

How can I find the stationary points of a multivariable function? For example: `f(x,y)= 3+ cos(x) sin(2y)`. I know that I've to set their partial derivatives to zero but how can I sovle the equation?

Thank you!

Answer

You will have a system, not an equation: `{((del f)/(del x)=-sin(x)sin(2y)=0),((del f)/(del y)=2cos(x)cos(2y)=0):}`