# Laplace inverse convolution

rj18
Homework Statement:
hey i was wondering if i could get some help with my maths i need to find the output using place and then convolution . i need to find out the step input response and how to use convolution to find output when input = [0,t<0 t,0<t<t1 t1,t<0<t2]

thanks
Relevant Equations:
Laplace equation was s^2+5s+8=(1/s+2)
inverse 1/4 e^(-2t)-1/4 e^(-2t)+e^(-2t)/2 t
find concolution when input = [0,t<0 t,0<t<t1 t1,t<0<t2]
e

rj18
i meant convolution*
and yes i have used convolution in problems that are shorter and much simpler. such as for the input t<0. but i don't know how to do it with more input variables such as 0<t<t1

Homework Helper
Gold Member
Homework Statement: hey i was wondering if i could get some help with my maths i need to find the output using place and then convolution . i need to find out the step input response and how to use convolution to find output when input = [0,t<0 t,0<t<t1 t1,t<0<t2]
That string of variables and commas etc. doesn't mean anything to me.
thanks
Homework Equations: Laplace equation was s^2+5s+8=(1/s+2)
Is that supposed to represent a transform of something? It doesn't make any sense as it is written.
inverse 1/4 e^(-2t)-1/4 e^(-2t)+e^(-2t)/2 t
find concolution when input = [0,t<0 t,0<t<t1 t1,t<0<t2]
What is that supposed to be the inverse of? Your post is hopelessly confusing. You could start by stating the original problem word for word.

• vela
rj18
So do you recall what the Laplace Transform of {f(t) • g(t) } is? Where I used the • to represent convolution.
This may help -
https://www.rapidtables.com/math/calculus/laplace_transform.html#Laplace transform properties
So do you recall what the Laplace Transform of {f(t) • g(t) } is? Where I used the • to represent convolution.
This may help -
https://www.rapidtables.com/math/calculus/laplace_transform.html#Laplace transform properties
That string of variables and commas etc. doesn't mean anything to me.

Is that supposed to represent a transform of something? It doesn't make any sense as it is written.

What is that supposed to be the inverse of? Your post is hopelessly confusing. You could start by stating the original problem word for word.

Sorry that i wasnt clear enough
i found the laplace transform and the impulse response i think.
i have given all the questions a go but not too sure

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