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A geometry problem by Mihir Srivastava

Geometry Level 1

Solve This \[cos 0^o×cos 1^o×cos 2^o×cos 3^o×cos 4^o \cdot\cdot\cdot\cdot\cdot cos 88^o×cos 89^o×cos 90^o\]

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by Mihir Srivastava

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