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Find the inverse Laplace transforms: F(s) = 1 / ((s + a)(s + b)) assuming a = b.

User Andy Wan
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Final answer:

The inverse Laplace transform of the function F(s) = 1 / ((s + a)(s + b)) with a = b is te-at, where a represents a constant.

Step-by-step explanation:

To find the inverse Laplace transform of F(s) = 1 / ((s + a)(s + b)) when a = b, we can use partial fraction decomposition. However, since a and b are equal, this becomes a special case known as repeated linear factors. We can write:

F(s) = A / (s + a)^2

To find A, we would normally differentiate both sides with respect to s, but in this case, we notice that setting A equal to 1 would be sufficient because the derivative of s + a is 1. Thus, F(s) simplifies to:

F(s) = 1 / (s + a)^2

The inverse Laplace transform of 1 / (s + a)^2 is t e-a t, where a represents a constant. Therefore, the inverse Laplace transform of our original function F(s) is:

L-1{F(s)} = t e-a t

User Mozman
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