Write the Expression in Terms of Sine and Cosine, and Simplify

question 33

Multiple Choice

Write the expression in terms of sine and cosine, and simplify so that no quotients appear in the final expression.
-10 cos 26° cos 13°

• A)5(sin 39° - sin 13°)
• B)10(sin 39° + sin 13°)
• C)5(cos 39° - cos 13°)
• D)5(cos 39° + cos 13°)

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Definitions:

Average Costs

The total cost of production divided by the quantity produced, often used to evaluate production efficiency.

Fixed Costs

Costs that remain constant regardless of the level of production or sales activities, such as rent, salaries, and insurance premiums.

Marginal Costs

Marginal costs represent the change in total production cost that arises when the quantity produced is incremented by one unit, essentially the cost of producing one additional unit of a good.

Marginal Productivity

Marginal productivity is the additional output that is produced by using one more unit of a certain input, assuming that all other inputs remain constant.