Home › AP EAPCET (Engineering) › Mathematics › Trigonometry: Trigonometric Ratios upto Transformations › Expand cos(A + B).
Expand cos(A + B).
AsinA cosB + cosA sinB
BsinA cosB − cosA sinB
CcosA cosB − sinA sinB
DcosA cosB + sinA sinB
Answer & Solution
Correct answer: C. cosA cosB − sinA sinB
Cosine of a sum subtracts the product of sines from the product of cosines.
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