\"\"

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Prove that \"\".

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The function is \"\".

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Since  \"\".

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Substitute \"\" in \"\".

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\"\".

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\"\"

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Definitions of Hyperbolic trigonometric functions : \"\" and \"\".

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\"\"

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\"\"

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\"\"

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\"\"

\

\"\"

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\"\"

\

\"\".

\

\"\".

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\"\"

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\"\".