Find the Exact Value of the Expression $$\cos ^ { - 1 } \left[ \cos \left( \frac { \pi } { 10 } \right) \right]$$

question 266

Multiple Choice

Find the exact value of the expression. Do not use a calculator.
- $$\cos ^ { - 1 } \left[ \cos \left( \frac { \pi } { 10 } \right) \right]$$

• A) \(\frac { \pi } { 10 }\)
• B) \(10 \pi\)
• C) \(- 10 \pi\)
• D) \(- \frac { \pi } { 10 }\)

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