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

question 40

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:

Comparative Advantage

The ability of a country, individual, company, or region to produce a good or offer a service at a lower opportunity cost than competitors.

Capital

Resources made and used by people to produce and distribute goods and services, including buildings, machinery, tools, and equipment.

Investment

Utilization of resources (such as capital, time, or effort) with the expectation of achieving a future return, often through the acquisition of assets or improvement of productivity.

Inefficiency

The state of not achieving maximum productivity; failing to make the best use of time, resources, or energy.