 
Summary: V1 1 2 3 4 5 6
Last Name:
First Name:
ID: Section:
Math 250 Midterm #2. October 8, 2004
Attention! Please, note that this is the closed book test. You are not allowed to use graphing
calculator. Simple calculators are allowed. Please, show all important steps in you solution but do
not make your solution excessively long.
1. (15pt) The equation of a surface Cartesian coordinates is
xy 
1
x2 + y2 + z2
= 1  x2 + y2.
Change this equation into Spherical coordinates.
2
2. Evaluate the limits of functions of two variables:
a) (10pt)
lim
(x,y)(0,0)
x4
