Find the Exact Value of the Expression, If Possible $\cos \left( \tan ^ { - 1 } \frac { 1 } { 5 } \right)$

question 210

Multiple Choice

Find the exact value of the expression, if possible. Do not use a calculator.
- $\cos \left( \tan ^ { - 1 } \frac { 1 } { 5 } \right)$

• A) \(\frac { 5 \sqrt { 26 } } { 26 }\)
• B) \(\frac { \sqrt { 26 } } { 5 }\)
• C) \(\frac { 5 } { 26 }\)
• D) \(\frac { 1 } { 5 }\)

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Definitions:

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The quantity of goods or services produced by a firm within a given time period.

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A period in economics where at least one factor of production is fixed and cannot be changed.

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