Topics · 2 identities

Power Reduction

Lowering the power of squared sine and cosine using double-angle identities.

sin² θ

sin2θ=1cos2θ2\sin^{2}\theta = \dfrac{1 - \cos 2\theta}{2}
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cos² θ

cos2θ=1+cos2θ2\cos^{2}\theta = \dfrac{1 + \cos 2\theta}{2}
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