Q6 Q21.) Verify the identity, write the left side numerator in terms of a sum or difference formula for sine or cosine, rewrite the expression found in the previous step by separating the denominator, and the expression from the previous step then simplifies to cot α - tan β using what?
Accepted Solution
A:
cos(α + β) = cosα*cosβ - sinα*sinβ
denominator remains the same for both expressions as sinα*cosβ