ctg x = 1 - t2 / 2t ( x sudut lancip ) maka sin 1/2 x adalah?

TriGonoMetRi

Hy Nabila... :)

cot x = (1 - t²) / 2t
tan x = 2t / (1 - t²)
tan 2(1/2 x) = (2 tan (1/2 x))/(1 - tan² (1/2 x))

Lihat kesamaan tempat nya..

tan 1/2 x = t =. sin (1/2 x) /cos (1/2 x) = t/1
r = √(t² + 1²) = √(1 + t²)

sin (1/2 x) = t/r = t/√(1 + t²) ✔