Use the Product-To-Sum Formulas to Rewrite the Product as a Sum

question 30

Multiple Choice

Use the product-to-sum formulas to rewrite the product as a sum or difference.​ $$10 \cos 45 ^ { \circ } \cos 20 ^ { \circ }$$ ​

• A)​ \(10 \left( \cos 25 ^ { \circ } + \cos 65 ^ { \circ } \right)\)
• B)​ \(\cos 25 ^ { \circ } + \cos 65 ^ { \circ }\)
• C)​ \(5 \left( \cos 65 ^ { \circ } - \cos 25 ^ { \circ } \right)\)
• D) \(5 \left( \cos 25 ^ { \circ } + \cos 65 ^ { \circ } \right)\)
• E)​ \(5 \left( \cos 65 ^ { \circ } + \sin 25 ^ { \circ } \right)\)

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Definitions:

EMG

Electromyography, a diagnostic procedure to assess the health of muscles and the nerve cells that control them.

Electrodes

Conductor materials used to establish electrical contact with a nonmetallic part of a circuit, often used in medical and scientific equipment.

Skeletal Muscle Fibers

Long, cylindrical cells that make up skeletal muscles, responsible for voluntary movements through contraction.

Nuclei

Structures within cells that contain the genetic material and act as control centers for cell growth, metabolism, and reproduction.