Question:medium

\[ \sin9^\circ\sin18^\circ\sin36^\circ\sin54^\circ\sin72^\circ\sin81^\circ \]

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Use angle pairing \( \theta + (90^\circ-\theta)=90^\circ \).

Updated On: Jun 22, 2026

\(\frac{10+2\sqrt5}{128}\)
\(\frac{5-\sqrt5}{128}\)
\(\frac{5-\sqrt5}{64}\)
\(\frac{10-2\sqrt5}{512}\) \bigskip

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The Correct Option is B

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