Solve the Equation on the Interval [0, 2π) $$\cos ^ { 2 } x + 2 \cos x + 1 = 0$$

question 144

Multiple Choice

Solve the equation on the interval [0, 2π) .
- $$\cos ^ { 2 } x + 2 \cos x + 1 = 0$$

• A) \(\pi\)
• B) \(2 \pi\)
• C) \(\frac { \pi } { 2 } , \frac { 3 \pi } { 2 }\)
• D) \(\frac { \pi } { 4 } , \frac { 7 \pi } { 4 }\)

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Definitions:

Variable Cost

Outlays that adjust in accordance with the volume of production or output, like materials and labor costs.

Loan

A sum of money that is borrowed and expected to be paid back with interest.

Economies of Scale

Refers to the cost advantage that arises with increased output of a product, leading to a reduction in the per-unit cost.

Marginal Cost

An alternative phrasing expressing the additional cost incurred from the production of the next unit of output.