Step 1: \

The trigonometric equation is $\"\"$ .

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$\"\"$

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General solution for $\"\"$ : $\"\"$

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$\"\"$

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The solution of the equation $\"\"$

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Step 2:

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$\"\"$ for the interval $\"\"$ .

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$\"\"$

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The solution of the equation

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$\"\"$ .

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Solution :

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(a)

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The solution of the equation $\"\"$

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(b)

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The solution of the equation

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$\"\"$ .

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