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Step 1 :

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The rate of change of V is proportional to V.

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$\"\"$

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Where k is proportionality constant..

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Rewrite the above equation :

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$\"\"$

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Apply integration on each side.

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$\"\"$

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When $\"\"$ .

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$\"\"$

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Substitute $\"\"$ in equation.

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$\"\"$ when $\"\"$ .

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$\"\"$

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Substitute $\"\"$ in equation (2).

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$\"\"$

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Substitute $\"\"$ in above equation.

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$\"\"$

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$\"\"$

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when $\"\"$

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Solution :

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when $\"\"$

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