Use an Addition or Subtraction Formula to Write $\cos 75 ^ { \circ } \cos 15 ^ { \circ } + \sin 75 ^ { \circ } \sin 15 ^ { \circ }$

question 77

Essay

Use an addition or subtraction formula to write $\cos 75 ^ { \circ } \cos 15 ^ { \circ } + \sin 75 ^ { \circ } \sin 15 ^ { \circ }$ and find its exact value.

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Definitions:

Demand for Resources

The desire and willingness to purchase or acquire resources based on their contribution to production or utility.

Output Increases

A rise in the amount of goods or services produced by a company or economy.

Price-taker Firm

A company that has no control over the market price and must accept the prevailing market price for its products.

Short Run

A period in economics during which some factors of production are fixed, limiting the ability to fully adjust to market changes.