$\"\"$

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The trigonometric equation is $\"\"$ .

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Consider $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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Apply pythagorean identity : $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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Apply zero product property.

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$\"\"$

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

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$\"\"$

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Consider $\"\"$ .

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$\"\"$

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The general solution of $\"\"$ is $\"\"$ , where $\"\"$ is an integer. \ \

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$\"\"$ .

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Find the solutions in the interval $\"\"$ .

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If $\"\"$ , $\"\"$ .

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If $\"\"$ , $\"\"$ .

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Thus, the solutions are $\"\"$ and $\"\"$ in the interval $\"\"$ .

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$\"\"$

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Consider $\"\"$ .

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$\"\"$

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The general solution of $\"\"$ is $\"\"$ , where $\"\"$ is an integer. \ \

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$\"\"$ .

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Find the solutions in the interval $\"\"$ .

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If $\"\"$ , $\"\"$ .

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If $\"\"$ , $\"\"$ .

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Thus, the solution is $\"\"$ in the interval $\"\"$ .

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The solutions are $\"\"$ , $\"\"$ , and $\"\"$ in the interval $\"\"$ .

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$\"\"$

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The solutions are $\"\"$ , $\"\"$ , and $\"\"$ in the interval $\"\"$ .