Summary: University of Regina
Department of Mathematics and Statistics
Math 213-001
Midterm - Sample answers
1. Find the local maximum and minimum values and saddle point(s) of the function.
f(x, y) = (y2
- x2
)ey
.
What can you say about the tangent plane at (0, -2)?
Answer. We first calculate the partial derivatives:
fx = -2xey
; fy = 2yey
+ (y2
- x2
)ey
= (y2
+ 2y - x2
)ey
Since the exponential is never zero, equating both partial derivatives to zero we get

Source: Argerami, Martin - Department of Mathematics and Statistics, University of Regina

Collections: Mathematics