We have to simplify: [cos x*sin(2x) - 2 sin x]/(sin x)^2
*cos x
[cos x*sin(2x) - 2 sin x]/(sin x)^2 *cos
x
use sin 2x = 2*sin x * cos
x
=> [2*(cos x)^2 *sin x - 2 sin x]/(sin x)^2 *cos
x
=> [2*(cos x)^2 - 2]/sin x *cos
x
=> [2*(cos x)^2/ sin x*cos x] - [2/sin x *cos
x]
=> [2*cos x/ sin x] - [4/ 2*sin x*cos
x]
=> [2*cos x/ sin x] - [4/ sin
2x]
=> 2*cot x - 4*cosec
2x
The required result is 2*cot x - 4*cosec
2x
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