Use a Double-Angle Formula or a Half-Angle Formula to Simplify $\sqrt { \frac { 1 + \cos 4 \pi } { 2 } }$

question 95

Essay

Use a double-angle formula or a half-angle formula to simplify $\sqrt { \frac { 1 + \cos 4 \pi } { 2 } }$ .

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Definitions:

Normal Distribution

A bell-shaped curve that represents the spread of a variable in a way that most occurrences take place around the central peak and the probabilities for values further away from the mean taper off equally in both directions.

Standard Deviations

A measure of the amount of variation or dispersion of a set of values relative to the mean.

Crystallized Intelligence

The ability to use learned knowledge and experience effectively.

Primary Mental Abilities

Fundamental skills and cognitive functions such as reasoning, memory, and perception that are considered essential for intelligence.