Use the Sum-To-Product Formulas to Select the Sum or Difference $\cos ( 5 \phi + 2 \pi ) + \cos 5 \phi$

question 123

Multiple Choice

Use the sum-to-product formulas to select the sum or difference as a product. $\cos ( 5 \phi + 2 \pi ) + \cos 5 \phi$

• A) \(- 2 \cos 5 \phi \cos \pi\)
• B) \(- 2 \cos 5 \pi\)
• C) \(2 \cos ( 5 \phi + \pi ) \cos \pi\)
• D) \(2 \cos ( \phi + \pi ) \cos \pi\)
• E) \(2 \cos ( 5 \phi + \pi )\)

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Definitions:

\(g(x)\)

Represents a function named g that is dependent on a variable x.

Graph

A visual outline that maps the structure of relationships or interconnections among a number of things using specific signs like dots, lines, and bars.

Horizontal Asymptote

A horizontal line that a graph approaches but never reaches as the independent variable approaches infinity or negative infinity.

\(4^{x+2}\)

An exponential expression indicating that four is raised to the power of x + 2, where x is a variable.