Question

-2sinx.cosx=-sin2x. How?

Answer 1

because it is a formula of trigonometry

2sinx.cosx= sin2x

Answer 2

★Heya★

WE KNOW THAT

Sin ( A + B ) = Sin A × Cos B + Cos A × Sin B

=>

R.H.S

- Sin 2x = - Sin ( x + x )

=>

- Sin ( 2x ) =

- { Sin x × Cos x + Cos x × Sin x }

=>

- Sin ( 2x ) = - 2 Sin x × Cos x