What is the identity of cos 2 θ

Hani Gotc asked Apr 25, 2023

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Hani Gotc asked Apr 25, 2023

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9 votes

Using the cosine double-angle identity. The cosine double angle formula tells us that cos(2θ) is always equal to cos²θ-sin²θ.

Majella answered Apr 29, 2023

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