(1-cosx)^1/2*(1+cosx)^1/2=sinx
=sqrt(1-cosx)*sqrt(1+cosx)
=sqrt(1-cos^2x)
=sinx
Is it acceptable? Thank You.
=sqrt(1-cosx)*sqrt(1+cosx)
=sqrt(1-cos^2x)
=sinx
Is it acceptable? Thank You.
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You got it. All I would do differently is show that 1 - cos(x)^2 is sin(x)^2
sqrt(1 - cos(x)^2) =
sqrt(sin(x)^2) =
sin(x)
But that's just a minor issue. You seem to understand what you're doing.
sqrt(1 - cos(x)^2) =
sqrt(sin(x)^2) =
sin(x)
But that's just a minor issue. You seem to understand what you're doing.
-
To Prove:-
(1- cosx)^1/2 * (1+ cosx)^1/2 = sinx
Left Hand Side :
(1- cosx)^1/2 * (1+ cosx)^1/2
= [ (1- cosx)* (1+ cosx)]^1/2
= [ 1 - cos^2x]^ 1/2, But [ (a- b )(a + b)] = a^2 - b^2
= [sin^2x]^1/2 , But (1- cos^2x) = sin^2x
= [sinx]^2*1/2,
= sinx = Right Hand Side
Hence Proved.
(1- cosx)^1/2 * (1+ cosx)^1/2 = sinx
Left Hand Side :
(1- cosx)^1/2 * (1+ cosx)^1/2
= [ (1- cosx)* (1+ cosx)]^1/2
= [ 1 - cos^2x]^ 1/2, But [ (a- b )(a + b)] = a^2 - b^2
= [sin^2x]^1/2 , But (1- cos^2x) = sin^2x
= [sinx]^2*1/2,
= sinx = Right Hand Side
Hence Proved.