Trigonometrymedium · Past Paper
What is the formula for cos(A - B)?
Acos A cos B - sin A sin B
Bcos A cos B + sin A sin B
Csin A cos B + cos A sin B
Dsin A sin B - cos A cos B
✓ Correct Answer: B — cos A cos B + sin A sin B
The cosine of a difference uses the addition of the product of cosines and the product of sines.
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