$\"\"$

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Prove that $\"\"$ .

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Consider $\"\"$ .

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Since the hyperbolic identity : $\"\"$ .

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$\"\"$ .

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Substitute $\"\"$ .

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$\"\"$

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$\"\"$ .

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Since $\"\"$ .

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Substitue $\"\"$ and $\"\"$ in the above equation

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$\"\"$ .

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Apply logirthm on each side .

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$\"\"$

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Since $\"\"$ .

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$\"\"$ .

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Substitue $\"\"$ in the above equation.

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$\"\"$ .

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$\"\"$

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$\"\"$ .