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Use the Laplace transform integral to prove that for any real constant k,L(kx(t))=kX(s)

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Final answer:

To prove L(kx(t)) = kX(s), start with the definition of the Laplace transform and apply the constant multiple rule, factoring out the constant k from the integral, resulting in the desired relationship.

Step-by-step explanation:

The student is asking how to prove that the Laplace transform of a scaled function kx(t) is equal to k times the Laplace transform of the function x(t), which is denoted kX(s). The proof involves using the definition of the Laplace transform which is an integral transform that takes a function of a real variable t (the time domain) to a function of a complex variable s (the frequency domain).

To prove this, consider the Laplace transform integral of the function kx(t) given by:

L(kx(t)) = ∫_{0}^{∞} e^{-st}kx(t) dt

Since k is a constant, it can be factored out of the integral:

L(kx(t)) = k ∫_{0}^{∞} e^{-st}x(t) dt

This is k times the Laplace transform of x(t), thus we get:

L(kx(t)) = kX(s)

Where X(s) is the Laplace transform of the function x(t).

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