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Step 1 :

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Definition of hyperbolic functions :

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1. $\"\"$ .

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2. $\"\"$ .

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Step 2 :

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(a)

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The function is $\"\"$ .

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Substitute $\"\"$ in $\"\"$

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$\"\"$

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Step 3 :

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(a)

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The function is $\"\"$ .

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Substitute $\"\"$ in $\"\"$

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$\"\"$

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Solution :

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(a) $\"\"$

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(b) $\"\"$

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