What Is the Laplace Transform of a Convolution?

rj18
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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
 
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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
 
rj18 said:
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.
 
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scottdave said:
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
scottdave said:
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
LCKurtz said:
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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There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...

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