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Rational fools

Geometry Level 3

\(A = \sin 15^\circ \\ B=\cos 15^\circ \\ C= \sin 15^\circ\cos 15^\circ \\ D = \sin 15^\circ\cos 75^\circ\)

Which of the following is/are rational?

\[B,C,D\] \[A,B\] Only \(D\) None of these Only \(C\) \[C,D\]

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by Nihar Mahajan

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