1, substitute x and y, f (0,1) = 0 2+12-E0 = 0+1-1= 0.

2. The point where the partial derivatives of function f to x and y are equal to 0 respectively is the stagnation point.

Taking y as a constant, we get f*(x)=2x+2=0 and x=- 1.

If x is regarded as a constant, f*(y)=2y=0, and y=0.

So the stagnation point is (-1, 0)

Hope to adopt ~