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Show that csc 2x + csc 4x + csc 8x + csc 16x + csc 32x = cot 32x |
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Answer» LEFT side: 1 sin 4 x − cos 4 x sin 4 x = 1 − cos 4 x sin 4 x = = ( 1 − cos 2 x ) ( 1 + cos 2 x ) sin 4 x = ( sin 2 x ) ( 1 + cos 2 x ) sin 4 x = 1 + cos 2 x sin 2 x = 1 sin 2 x + cos 2 x sin 2 x =
= csc 2 x + cot 2 x |
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