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A geometry problem by Sabhrant Sachan

Geometry Level 2

\[ \large 81^{\sin^2 x} + 81^{\cos ^2 x} = 30 \]

Which of the following values is a possible value of \(x\) satisfying the equation above?

\[\dfrac{7\pi}{18}\] \[\dfrac{5\pi}{18}\] \[\dfrac{\pi}3\] \[\dfrac{\pi}2\] \[\dfrac{\pi}4\] \[\dfrac{\pi}{15}\]

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by Sabhrant Sachan

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