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Prove: sin(α−β)=sinαcosβ−sinβcosα

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Final answer:

The identity sin(α-β) = sinαcosβ - cosαsinβ can be proved using the sine sum and difference formulas, specifically the difference case, demonstrating the correctness of this trigonometric identity.

Step-by-step explanation:

The equation sin(α-β)=sinαcosβ-sinβcosα is a trigonometric identity that can be proved using the sum and difference formulas for sine.

Proof of Sin(α-β)

Start with the sum and difference formulas:

sin(α±β) = sinαcosβ ± cosαsinβ

For the subtraction case (α-β), the formula becomes:

sin(α-β) = sinαcosβ - cosαsinβ

This is the identity we set out to prove, and it is now evident that it holds true based on the established sum and difference formulas for sine.