\"\"

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\"\" for \"\", where \"\" and \"\" are constants.

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Consider \"\", such that \"\".

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If \"\", then \"\" for all values of \"\".

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\"\".

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Multiply on each side by \"\".

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\"\"

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Find the integral \"\".

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Definition of improper integral type 1:

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\"\".

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\"\"

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\"\"

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If \"\", then \"\".

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\"\"

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Thus, \"\" is a finite number .

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\"\" is convergent by the definition of improper integral of type 1.

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By comparison theorem , \"\" is also convergent.

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Therefore,  Laplace transform \"\" exists for every \"\".

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\"\"

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Laplace transform \"\" exists for every \"\".