dik tan x = 4/3 tentukan sin 1/2x

Pytagoras atau pake rumus identitas bisa.. Nanti didapat (tangen = depan/samping)

Cos x = 3/5

Cos x = 1 - 2sin^2 1/2x
3/5 = 1 - 2 sin^2 1/2x

sin^2 1/2 x = 1/5
sin 1/2x = 1/akar 5