Question

verify for sqrt(1-cosx)= sin/sqrt(1+cosx).

I multiplied the right side by sqrt(1-cosx) and got sqrt(1-cosx)= sin*sqrt(1-cosx), but I don't know what to do with the sin.

Answer 1

square both sides.

(1-cosx)=sin^2/(1+cosx)
multiple both sides by 1+cosx

1-cos^2 x = sin^2 x
sin^2x=sin^2x

Answer 2

Aren't you are only supposed to work on one side of the equation at a time? So you can't square or multiply both sides.

Answer 3

Ok ...

RS = sinx/√(1+cosx) * √(1-cosx)/√(1-cosx) , you did that
= sinx √(1-cosx) /(√( (1+cox)(1-cosx) )
= sinx √(1-cosx)/√(1 - cos^2 x)
= sinx √(1-cosx)/√sin^2 x
= sinx √(1-cosx)/sinx
= √(1-cosx)
= LS