critical point for f(x,y)=x+y?

Favorite Answer

from the wiki:

For a differentiable function of several real variables, a critical point is a value in its domain where all partial derivatives are zero. The value of the function at a critical point is a critical value.

The partial derivatives for this function of 2 variables, f, at an arbitrary point (x,y) is:

∂f/∂x = 1
��f/∂y = 1

So the partial derivatives are nowhere zero and so cannot be zero simultaneously.
So no critical points exist for this function....Show more

f(x,y) = x + y
fx = 1
fy = 1
no critical point...Show more

There are none, it's a plane....Show more