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Nonagon Property!

Geometry Level 2

\[\large \sec^{2} \left ( \dfrac{\pi}{9} \right ) + \sec^{2} \left (\dfrac{2 \pi}{9}\right) + \sec^{2} \left (\dfrac{4 \pi}{9}\right) = \, ? \]

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Excel in math and science

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by Danish Ahmed

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