Express the Sum or Difference as a Product of Sines $\cos ( 6 \theta ) + \cos ( 4 \theta )$

question 11

Multiple Choice

Express the sum or difference as a product of sines and/or cosines.
- $\cos ( 6 \theta ) + \cos ( 4 \theta )$

• A) \(2 \cos ( 5 \theta ) \sin \theta\)
• B) \(2 \cos ( 5 \theta ) \cos \theta\)
• C) \(2 \cos ( 5 \theta )\)
• D) \(2 \sin ( 5 \theta ) \sin \theta\)

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Definitions:

Aromatic Ring

A stable ring-shaped molecule made up of alternating single and double bonds, common in many organic compounds.

O,p-director

Substituents that direct incoming substituents to the ortho and para positions in an aromatic ring during electrophilic substitution reactions.

Major Organic Product

The predominant compound produced through an organic reaction, usually of greatest interest or utility.

Cyano Substituent

A cyano substituent refers to a group containing a carbon triple-bonded to a nitrogen atom (-C≡N) attached to a molecular framework.