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

Limit of (1-cos(x))/x as x approaches 0 | Derivative rules | AP Calculus AB | Khan Academy

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

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

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

Integral of 1/(1 + cos x) dx

1/(1+cosx) + 1/(1-cosx) = 2csc^2(x), verify the identity

Prove 1/cosx=tanx/sinx

Limit (1 - cosx)/x^2 At times L'Hospital's Rule may not be applied

What is `underset(xto0)lim(2(1-cosx))/(x^(2)` equal to?

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

#Trigonometry all formulas

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

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

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

Trigonometry Class 10 | Trigonometry Identities| Trigonometry Formulas #fun #shorts #youtubeshorts

Integral 1/(cos(x) - 1)

Proof that, as x tends to 0, the limit ((1 - cosx)/x) = 0

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

Prove that 1 - cosx = 2sin²x/2