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if theta frac pi 9 then 1 27 tan 2 theta 33 tan 4
Question:
If \( \theta = \frac{\pi}{9} \), then \( 1 + 27 \tan^2 \theta - 33 \tan^4 \theta + \tan^6 \theta = \)
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Recognize symmetric polynomial identities and known angle values to evaluate directly.
AP EAPCET - 2023
AP EAPCET
Updated On:
May 15, 2025
\( 3 \)
\( \mathbf{4} \)
\( -3 \)
\( -11 \)
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The Correct Option is
B
Solution and Explanation
Let \( x = \tan \theta \). Given: \[ 1 + 27x^2 - 33x^4 + x^6 \] Use substitution: \( x = \tan \frac{\pi}{9} \). Now plug into the expression and simplify or use known identity evaluation: \[ \text{Expression evaluates to } 4 \]
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