If A = 45 , verify that cos 2A = 2 cos^2 A – 1 = 1 – 2 sin^2 A

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A = 45 , verify that cos 2A = 2 cos^2 A – 1 = 1 – 2 sin^2 A

If A = 45^∘ , verify that(1) sin 2A = 2sin A cos A ,(2) cos 2A = 1,

If A=45∘, verify that: cos2A=2cos2A−1=1−2sin2A