Use the Given Information to Compute $\cos \left( \frac { \theta } { 2 } \right)$

question 20

Multiple Choice

Use the given information to compute $\cos \left( \frac { \theta } { 2 } \right)$ . $\cos \theta = \frac { 4 } { 7 }$ and $\frac { 3 \pi } { 2 } < \theta < 2 \pi$

• A) \(- \frac { 14 } { 15 }\)
• B) \(- \frac { \sqrt { 154 } } { 14 }\)
• C) \(\frac { \sqrt { 143 } } { 14 }\)
• D) 4/15
• E) \(\frac { \sqrt { 77 } } { 15 }\)

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Definitions:

Potassium Ions

Charged particles of potassium, a crucial mineral that plays key roles in cell function, including heart rhythm, muscle contraction, and nerve transmission.

Chloride Ions

Negatively charged particles (ions) that play key roles in maintaining cell stability, transmitting nerve impulses, and regulating fluid inside and outside of cells.

Sodium-Potassium Pump

A crucial cellular mechanism that moves sodium ions out of and potassium ions into cells, vital for maintaining cellular function and electrochemical gradients.

Intracellular

Relating to or occurring within a cell, encompassing the events, reactions, and processes in the cellular interior.