Use the Sum-To-Product Formulas to Rewrite the Sum or Difference $\sin 9 \theta + \sin 7 \theta$

question 79

Multiple Choice

Use the sum-to-product formulas to rewrite the sum or difference as a product. $\sin 9 \theta + \sin 7 \theta$

• A) \(2 \sin 8 \theta \sin \theta\)
• B) \(2 \cos 8 \theta \cos \theta\)
• C) \(2 \sin 8 \theta \cos \theta\)
• D) \(2 \cos 8 \theta \sin \theta\)
• E) \(2 \sin 9 \theta \cos 7 \theta\)

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Definitions:

Compound

A distinct chemical substance resulting from the combination of multiple elements into a molecule, exemplified by its specific chemical formula and molecular structure.

Cyclic Esters

Organic compounds characterized by a ring structure containing an ester linkage, also known by the term "lactones."

Lactones

Cyclic esters formed by the intramolecular reaction of a hydroxy acid, commonly found in various natural products and fragrances.

Cyclohexyl Formate

An organic ester derived from cyclohexanol and formic acid, known for its use in fragrance and flavor compositions.