Math*2270, Fall 2012
Due Wednesday, September 19 in class
▯ Ensure that your name and ID Number are clearly printed on the front page.
▯ You are encouraged to work with your friends to complete the assignment, but please write
up your ▯nal solutions on your own.
▯ Submit your assignment in class on or before the due date.
▯ This assignment carries a full weight of 4% of your ▯nal grade. Late submissions will be
given a zero.
1. For all of the following di▯erential equations, perform the following:
(i) State which variables are dependent and independent for the problem.
(ii) Give the order of the DE.
(iii) State whether the DE is linear or nonlinear.
a) sin(x)y + cos(x)y + tan(x)y = cot(x) + csc(x) + sec(x)
b) x (t) + x (t) = t
c) x + f = 0
d) dx = lnjx + x + e + e jx2 2. Verify that y = is a solution to
< ▯2e ▯x; x < 0
y ▯ y =
: 0; x ▯ 0
on each of the intervals (▯1;0) and (0;1). (Hint: Think o