Jawabanmu

2014-05-25T15:11:29+07:00
1-cos x/ x . tan x
= 1-(1-2sin²1/2x) / x . tan x
= 2 sin² 1/2x / x . tan x
= sin² 1/2x / (1/2x)² × x / tan x × 2 (1/2x)² / x . x
= 1 . 1 . 2 (1/4x²) / x²
= 1/2