Choose the One Alternative That Best Completes the Statement or Answers

question 277

Multiple Choice

Choose the one alternative that best completes the statement or answers the question.
Express the product as a sum containing only sines or cosines.
- $\cos ( 5 \theta ) \cos ( 4 \theta )$

• A) \(\frac { 1 } { 2 } [ \cos ( 9 \theta ) - \cos \theta ]\)
• B) \(\frac { 1 } { 2 } [ \cos \theta + \cos ( 9 \theta ) ]\)
• C) \(\cos ^ { 2 } \left( 20 \theta ^ { 2 } \right)\)
• D) \(\frac { 1 } { 2 } [ \cos ( 9 \theta ) - \sin \theta ]\)

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Supply Department

The department within an organization responsible for the procurement and management of goods and services required for its operations.

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