How on earth is 1-cos(x) equal to 2sin^2(x/2)?

1-cosx = 2sin^2(x/2) trigonometric identites proof || 1-cos theta

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Prove that 1+cosx=2cos^2(x/2) and 1-cosx=2sin^2(x/2) trigonometric identites

Why does sine squared plus cosine squared equal 1?

Limit of (1-cos(x))/x as x approaches 0 | Calculus 1

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Proof of the Limit (1-cosx)/x as x approaches 0

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Verify the Trig Identity (1 + cos(x))/sin(x) = csc(x) + cot(x)

Prove the Limit as x Approaches 0 of (1-cos(x))/x

Integral of 1/(1 + cos x) dx

PreCalculus - Trigonometry: Trig Identities (31 of 57) Proof cos^2(x)=(1+cos2x)/2

Prove (1 - sin x)/cos x = cos x / 1 + sin x

1+cosx=2cos^2(x/2) trigonometry identites solve || 1+cos(theta)

Integral of 1/(1+cos(x) vs integral of sqrt(1+cos(x))

Trigonometric Identity sinx/(1 + cos) = (1 - cosx )/sinx

Prove that 1 - cosx = 2sin²x/2

Six Trigs in 60 Seconds! #math #trigonometry

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