We observe that the Laplace inverse of this function will be periodic, with period T.

This is because of the part:

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We find the function for the first period [f1(t)] by ignoring the (1 − e-sT) part:

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Now

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Considering the second fraction, we have:

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which we can think of as:

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So

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which is in the form:

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where a = T.

So we can use Rule (4) again:

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This gives $g(t-T)=e^{t-T}$

Using Rule (4):

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So


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So the periodic function with $f(t)=f(t+T)$ has the following graph:


7_lap_invlaptrans_18pt__111.png