EGR 265, TEST I 1
EGR 265, Math Tools for Engineering Problem Solving
February 13, 2013, 50 minutes
TEST I
Name: ..........................................
Problem 1
Problem 2∗
Problem 3
Problem 4
Problem 5
Problem 6
Problem 7
Total
EGR 265, TEST I 2
Problem 1 (4+4+4+4 Points)
Determine the order of the following ODEs. Also, state if they are linear or non-linear.
(a) y′′ −y2=x
(b) y(3) −y′=xy
(c) x
y=y′
(d) (y′ex)′= cos x
Problem 2∗(8 Points Bonus)
Find the values of the constant cfor which the function y=c
x2is a solution of the differential
equation
xy′+y=x2y2.
Warning: This DE is neither separable nor linear, thus we don’t have a method to systemat-
ically find its solutions.