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

1 - cos x = 2sin^2(x/2)

微積分学入門 - 三角法：三角関数の等式（57問中30問）証明 sin^2(x)=(1-cos2x)/2

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

why sin(2x)=2sin(x)cos(x)

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

1-cosx formula || how to prove 1-cosx = 2sin^2(x/2) || trigonometry identities proof || my academy

cos 2x = 1 - 2sin^2 x

#integration miscellaneous exercise class 12

1/2sin(x)+cos(x) の積分　パターンにはめて解く　基礎から学ぶ微積分問題

1/2sin(x)+cos(x)の積分　三角関数の合成でさっと解く　基礎から学ぶ微積分問題

三角恒等式: cos(2x) = 1 - 2sin^2(x)

Evaluate: lim(x→0) (1-cosx^2)/(x^2 sinx^2) | limit x tend to 0 (1-cosx^2)/(x^2.sinx^2) indeterminate

Prove that 1 - cosx = 2sin²x/2

1-cos2x=2sin^2x and 1+cos2x=2cos^2x trigonometry solve

`int(sin2x+sin5x-sin3x)/(cosx+1-2sin^2 2x)dx`

proof that sin^2(x)=(1-cos2x)/2 || 1-cos2x=2sin^2 x

【標準】信州大 √(1-cosx)の積分

Evaluate: lim(x→0) (1-cosx^2)/(x^2 sinx^2)

Prove that 1-cos(2x) =2sin^2(x) || CBSE || ICSE ||