
Parviz F. answered 04/05/14
Tutor
4.8
(4)
Mathematics professor at Community Colleges
Can be proven by Cross Multiplication
1 + CosX = Sin X
Sin X 1 - CosX
( 1 +CosX ) ( 1 - Cos X) = Sin2 X
1 - Cos 2 X = Sin 2X
Sin 2 X = Sin 2 X
Otherwise right hand side has to be multiplied by ( 1-cosX ) / ( 1 -cosX )

Steve S.
04/06/14