Use a Double Angle Formula to Rewrite the Given Expression $$10 \cos ^ { 2 } x - 5$$

question 23

Multiple Choice

Use a double angle formula to rewrite the given expression. $$10 \cos ^ { 2 } x - 5$$

• A) \(5 \cos 5 x\)
• B) \(5 \cos 2 x\) ​
• C) \(10 \cos 2 x\) ​
• D) \(2 \cos 10 x\) ​
• E) \(2 \cos 5 x\) ​

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Definitions:

Highest Frequency

The maximum rate at which a wave varies, often associated with the concept of the highest pitch in sound or the highest rate of photon vibration in light.

Brain Waves

The rhythmic electrical activity produced by the brain, which can be measured using an electroencephalogram (EEG).

Normal Adult

Typically refers to a fully developed and mature human being usually characterized by completed physical growth and developed cognitive abilities.

EEG

Electroencephalogram, a test that detects electrical activity in the brain using small electrodes attached to the scalp.