OpenStax, Algebra and Trigonometry 2e §9.3 Double-Angle, Half-Angle, and Reduction Formulas · Exercise 63 · Trigonometry · Compound & multiple angles

Double-Angle, Half-Angle, and Reduction Formulas · Exercise 63

Prove the identities.

$cos (16 x) = (co s^{2} (4 x) - s i n^{2} (4 x) - s in (8 x)) (co s^{2} (4 x) - s i n^{2} (4 x) + s in (8 x))$

~11 minWritten answer · compare with the solution

OpenStax, Algebra and Trigonometry 2e · §9.3 Double-Angle, Half-Angle, and Reduction Formulas · Exercise 63

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