yuko-ogura SG start from RHS.. RHS=tan^2 x sin^2 x = (sec^2 x - 1) (sin^2 x) = (1/(cos^2 x) - 1) (sin^2 x) = (tan^2 x - sin^2 x) = (tan x + sin x) (tan x - sin x) = LHS
yuko-ogura SG no la..wad i meant..was dat yuan lai ur maths hw is done by the forumites one. jia you ba..jc life quite fun.
CoolMyth SG Using (a - b)(a + b) = a^2 - b^2 (cosec x -1) (cosec x + 1) ( sec x -1) ( sec x + 1) = 1 LHS = (cosec x -1) (cosec x + 1) ( sec x -1) ( sec x + 1) = (cosec^2 x -1)(sec^2 x -1) = (cot^2 x)(tan^2 x) = 1 = RHS
