Express the Sum or Difference as a Product $\cos 8 x - \cos 4 x$

question 143

Multiple Choice

Express the sum or difference as a product.
- $\cos 8 x - \cos 4 x$

• A) \(- 2 \sin 6 x \sin 2 x\)
• B) \(2 \cos 6 x \cos 2 x\)
• C) \(- 2 \cos 6 x \sin 2 x\)
• D) \(2 \cos 2 x\)

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Definitions:

Contract

A legally binding agreement between two or more parties, outlining obligations and rights.

Substantial Performance

A legal principle indicating that a party has fulfilled enough of its contractual obligations to warrant payment, even if minor details were not completed as specified.

Conditional Contract

An agreement where the obligations or terms are only to be fulfilled if certain conditions are met.

Condition Concurrent

A situation in a contract wherein the parties involved must perform their respective obligations at the same time.