Graduate Initial value ODE with shifting forcing function

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The discussion focuses on solving an initial value ordinary differential equation (ODE) using the Laplace Transform. The user derived the equation V(s) = [U(s+5) + 1] / (s - 12) and seeks assistance with the inverse transformation, specifically for U(s+5) / (s - 12). Participants clarify that U(t) represents the Heaviside step function, which has a known Laplace transform. They suggest applying the shifting property to find the Laplace transform of e^(at) * u(t), confirming that the transform of e^(-5t) * u(t) is 1 / (s + 5). The conversation emphasizes the importance of using standard Laplace transform tables for accurate calculations.
Houeto
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Use laplace Transform to solve this ode:
upload_2016-7-21_21-49-59.png


So I got:

sV(s)-V(0)-12V(s)=U(s+5)
V(s)(s-12)=U(s+5)+1
V(s)=[U(s+5)+1]/(s-12)

Now to go back to time domain with Inverse Laplace Transform...My question is, how to transform U(s+5)/(s-12)?

Any help?

Thanks guys
 
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I think it may help you to know that u(t) is the standard symbol for the step function, which has a known Laplace transform. Check your tables.
 
Thanks
 
@Twigg , can you shed some lights on Laplace Transform of e^(at)*u(t)?

Thanks
 
I'm pretty sure you just apply the shifting property to the Laplace transform of the Heaviside step function. The Laplace transform of ##u(t)## is ##\frac{1}{s}##, so the Laplace transform of ##e^{-5t} u(t)## is ##\frac{1}{s + 5}##. Just like you did in your first post.
 
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