Use an Identity to Write the Expression as a Single $2 \cos ^ { 2 } 22.5 ^ { \circ } - 1$

question 62

Multiple Choice

Use an identity to write the expression as a single trigonometric function or as a single number.
- $2 \cos ^ { 2 } 22.5 ^ { \circ } - 1$

• A) \(\sqrt { 3 }\)
• B) \(\frac { \sqrt { 2 } } { 4 }\)
• C) \(\frac { \sqrt { 3 } } { 3 }\)
• D) \(\frac { \sqrt { 2 } } { 2 }\)

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Definitions:

Contaminated Equipment

Tools or materials that have been exposed to harmful substances, bacteria, or pathogens, posing a risk of infection.

Immunoglobulin Levels

The concentration of immunoglobulins, which are antibodies in the blood plasma, indicating the health of the immune system and its ability to respond to pathogens.

Upper Respiratory Infection

An infection that affects the nasal passages, throat, and airways, commonly known as the common cold.

IgA

Immunoglobulin A, a type of antibody that plays a crucial role in the immune function of mucous membranes.