12
QuizMultiple Choice
Solving Trigonometric Equations — Unit test
Question 12 of 15 • Precalculus
Review the proof of cos(A - B) = cosAcosB + sinAsinB.Step 1: Step 2: Step 3: Step 4: Step 5:Step 6:Step 7:
Answer
A
1 and 1B
2 and 1C
(cosAcosB)2(sinAsinB)2 and (cos2(A – B))((sin2(A – B))D
(cos2A + sin2A)(cos2B + sin2B) and (cos2(A – B))(sin2(A – B))