1. cos п/5 *cosп/20 -sin п/5 *sin п/20 2. sin2x cos3x-2sin5x+cos2x sin3x 3. cos2,5x...

Question

1. cos п/5 *cosп/20 -sin п/5 *sin п/20
2. sin2x cos3x-2sin5x+cos2x sin3x
3. cos2,5x cos1,5x+cosx+sin1,5x sin2,5x

Answer 1

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