Step 1:

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$\"\"$ .

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Double-angle formula : $\"\"$ .

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Substitute $\"\"$ .

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$\"\"$

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$\"\"$ .

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Solution: \ \

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$\"\"$ .

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Step 1:

\

$\"\"$ .

\

$\"\"$ .

\

Double-angle formula : $\"\"$ .

\

$\"\"$ .

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

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$\"\"$ .

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

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$\"\"$

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$\"\"$ .

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Solution:

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$\"\"$ .

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\

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The exact values of $\"\"$ , and $\"\"$ .