Victor Camocho
math2250fall2011-2
WeBWorK assignment number Homework 11 is due : 11/10/2011 at 11:00pm MST.
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1. (1 pt) Library/274/Laplace3/prob1.pg
Find the Laplace transform of
(
0,
t <2
f (t) =
(t − 2)4 , t ≥ 2
F(s) =
4. (1 pt) Library/274/Laplace4/prob46.pg
Take the Laplace transform of the following initial value and
solve for Y (s) = L {y(t)}:
y00 + 9y = R(t)
y(0) = 0, y0 (0) = 0
Where R(t) = sin(πt),
R(t + 1) = R(t).
.
Y (s) =
Graph of R(t) (a rectified sine wave function):
.
2. (1 pt) Library/274/Laplace3/prob3.pg
Find the Laplace transform of


t <2
0,
f (t) = 2 sin(πt), 2 ≤ t < 3


0,
t ≥3
F(s) =
.
3. (1 pt) Library/274/Laplace4/prob44.pg
Take the Laplace transform of the following initial value problem and solve for Y (s) = L {y(t)}:
y00 − 8y0 − 9y = S(t)
y(0) = 0, y0 (0) = 0
(
1, 0 ≤ t < 1
Where S(t) =
,
S(t + 2) = S(t).
0, 1 ≤ t < 2
Y (s) =
.
The graph of S(t) (a square wave function):
5. (1 pt) Library/274/Laplace/prob11.pg
Find the inverse Laplace transform of
8s + 5
s2 + 21
y(t) =
1
s>0
.
c
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Team, Department of Mathematics, University of Rochester
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