Linear systems diff eq question

AI Thread Summary
The discussion revolves around solving the differential equation y' + 4y = 8x, with the assumption that x(t) is an impulse function. Participants clarify that the equation should actually be y' + 4y = δ(x), where δ(x) represents the Dirac delta function. There is a query about whether initial conditions were provided, with a common assumption being y(0-) = 0. One participant expresses uncertainty and plans to consult a differential equations textbook for further understanding. The conversation highlights the importance of correctly interpreting the equation and initial conditions in solving linear systems.
sdusheyko
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given x(t)=impulse
find y(t)

y(prime)=4y=8x

i am lost
 
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I assume there's a typo in your post and the differential equation is actually y'+4y=8x, so you want to solve

y'+4y=\delta(x)

where \delta(x) is the Dirac delta function. Is this right? Did the problem specify an initial condition? (Engineers typically assume y(0-)=0.)
 
vela said:
I assume there's a typo in your post and the differential equation is actually y'+4y=8x, so you want to solve

y'+4y=\delta(x)

where \delta(x) is the Dirac delta function. Is this right? Did the problem specify an initial condition? (Engineers typically assume y(0-)=0.)

you're right about everything you've said. I'm going to stick my head in a diff eq book and if i get lost i'll probably come back and whine.

thanks
 
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