\"\"

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The trigonometric equation is \"\".

\

\"\"

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Quotient identity : \"\".

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\"\"

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Apply zero product property.

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\"\" or \"\"

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\"\" or \"\".

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\"\"

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Solve \"\".

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\"\"

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

\

The solution is \"\", where \"image\" is an integer.

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Find the solutions on the interval \"\".

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If \"\", \"\".

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If \"\", \"\".

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If \"\", \"\".

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Thus, the solutions are \"\", \"\", and \"\" on the interval \"\".

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\"\"

\

Solve \"\".

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\"\"

\

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

\

The solution is \"\", where \"image\" is an integer.

\

Find the solutions on the interval \"\".

\

If \"\", \"\".

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If \"\", \"\".

\

Thus, the solutions are \"\" and \"\" on the interval \"\".

\

Therefore, the solutions of \"\" are \"\", \"\"\"\", \"\", and \"\" on the interval \"\"

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Observe the given options :

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\"\" is not a solution of \"\".

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Option D is the corrrect choice.

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\"\"

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Option D is the corrrect choice.