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Sum and Difference Formulas
Worksheet
Grade Level
Pre-Calculus
Pre-CAL.85 Sum and Difference Formulas
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Skill Level
🔴 Hard
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Simplify: cos(a + b) + cos(a − b).
A
2 sin a sin b
B
−2 sin a sin b
C
2 sin a cos b
D
2 cos a cos b
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