1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Laplace Transform

  1. Mar 14, 2009 #1
    1. The problem statement, all variables and given/known data

    y''+y = f(t)

    y(0) = 0; y'(0)=1

    f(t) = 1, 0<=t<pi/2
    0, pi/2<=t

    3. The attempt at a solution
    so far, i have

    (s^2+1)*L{y} = [tex]\frac{s-e^(-pi/2s)}{s}[/tex] +1

    what is next ?
  2. jcsd
  3. Mar 14, 2009 #2


    User Avatar
    Homework Helper
    Gold Member

    That doesn't look quite right; the Laplace Transform of [itex]f(t)[/itex] is not [tex]\frac{s-e^{-\pi s/2}}{s}[/tex] (although it's close). Double check that calculation.

    Once you correct your expression, solve for [itex]\mathcal{L}[y(t)][/itex] and then take the inverse Laplace transform to get [itex]y(t)[/itex]
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook