Find the Exact Value of the Expression $\cos ^ { - 1 } \left[ \cos \left( - \frac { 3 \pi } { 5 } \right) \right]$

question 385

Multiple Choice

Find the exact value of the expression. Do not use a calculator.
- $\cos ^ { - 1 } \left[ \cos \left( - \frac { 3 \pi } { 5 } \right) \right]$

• A) \(- \frac { 3 \pi } { 5 }\)
• B) \(\frac { 2 \pi } { 5 }\)
• C) \(\frac { 3 \pi } { 5 }\)
• D) \(- \frac { 2 \pi } { 5 }\)

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Definitions:

Systole

The phase of the cardiac cycle during which the heart muscle contracts, resulting in the ejection of blood into the systemic circulation.

Ventricular Excitation

The process of electrical activation of the ventricles of the heart, leading to their contraction.

ECG

A test that records the electrical activity of the heart to detect heart conditions.

ECGs

Electrocardiograms, a medical test that measures the electrical activity of the heart to identify abnormalities.