- #1
Mark Brewer
- 38
- 4
Homework Statement
L-1{(2s2+3)/(s2+3s-4)2}
The Attempt at a Solution
I factored the denominator
f(t)=(2s2+3)/((s-1)(s+4))2
now I've tried partial fractions to get
(2s2+3)/((s-1)(s+4))2 = A/(s-1)2 + B(s+4)2
(2s2+3)=A(s+4)2 + B(s-1)2
by substitution, s=1 and s=-4
5=A(25)
A=1/5
35=B(25)
B=7/5
(1/5) 1/(s-1)2 + (7/5) 1/(s+4)2
At this point I'm not sure if I am on the right track, but I did start to see some identities that may help.
1/5 L-1{1/(s-1)2} +7/5 L-1{1/(s+4)2}
I'm starting to see a pattern for n!\sn+1 and eat
Am I on the right track, or did I go on a tangent?
Any help would be appreciated!