Complete the Identity $\cos ( \alpha + \beta ) + \cos ( \alpha - \beta ) =$

question 195

Multiple Choice

Complete the identity.
- $\cos ( \alpha + \beta ) + \cos ( \alpha - \beta ) =$ ?

• A) \(2 \cos \alpha \cos \beta\)
• B) \(\cos \alpha \cos \beta\)
• C) \(2 \sin \alpha \cos \beta\)
• D) \(\sin \beta \cos \alpha\)

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