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The differential equation is $\"\"$ , $\"\"$ .

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$\"\"$ .

Apply integral on each side.

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

Find the constant.

Initial condition is $\"\"$ .

Substitute $\"\"$ and $\"\"$ in $\"\"$ .

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

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$\"\"$ .

The solution of differential equation is $\"\"$ . $\"\"$

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