Step 1;

The differential equation is .

Rewrite the equation is .

Apply integration on each side.

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Using integration sum rule .

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Using integration rule .

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Using integration rule .

Using integration trigonometric rule .

The equation is .

Step 2:

Find constant value.

The condition .

Substitute and in equation.

The equation is .

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The condition , then .

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The solution of differential equation is .

Solution:

The solution of differential equation is .