Write the Product as a Sum $\cos 7 x \cos 3 x$

question 27

Multiple Choice

Write the product as a sum. $\cos 7 x \cos 3 x$

• A) \(\cos 7 x + \cos 3 x\)
• B) \([ \cos 7 x + \cos 3 x ] / 2\)
• C) \([ \cos 10 x + \cos 4 x ] / 2\)
• D) \(- [ \cos 10 x + \cos 2 x ] / 2\)
• E) none of these

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Definitions:

Peptidoglycan

A polymer consisting of sugars and amino acids that forms a mesh-like layer outside the plasma membrane of most bacteria, providing structural support and giving the bacterial cell wall its rigidity.

Chlorophyll

A vital photosynthetic green pigment present in the chloroplasts of plants, algae, and certain bacteria.

Chlamydia

Chlamydia is a sexually transmitted infection caused by the bacterium Chlamydia trachomatis, leading to various health problems if untreated.

Mycobacteria

A genus of Actinobacteria, many species of which are pathogenic and cause diseases such as tuberculosis and leprosy.