Express cot(2x): Express cot(2x) in terms of sine and cosine.Cotangent is the reciprocal of tangent, which is sine over cosine. Therefore, cot(2x) can be written as sin(2x)cos(2x).
Use Pythagorean identity: Use the Pythagorean identity to express sin(2x) in terms of cos(2x). The Pythagorean identity states that sin2(θ)+cos2(θ)=1. We can solve for sin(2x) by rearranging the identity to sin2(2x)=1−cos2(2x) and then taking the square root.
Express sin(x): Express sin(x) in terms of sin(2x) and cos(2x) using the double angle formula.The double angle formula for sine is sin(x)=2⋅sin(2x)⋅cos(2x).
Substitute into formula: Substitute the expression for cot(2x) into the double angle formula.Since cot(2x)=sin(2x)cos(2x), we can write sin(x) as sin(x)=2⋅sin(2x)⋅(sin(2x)1)⋅cot(2x).
Simplify sin(x): Simplify the expression for sin(x). The sin(2x) terms cancel out, leaving us with sin(x)=2⋅cot(2x). Since cot(2x) is given as a, we have sin(x)=2a.
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