Question

Write the maximum and minimum values of cos (cos x).

 

Answer 1

We know: 

\[ - 1 \leq \cos x \leq 1\]

\[\text{ Also,} \cos\left( - \theta \right) = \cos\theta\]

\[\text{ When the angle increases from 0 to }\frac{\pi}{2}, \text{ the value of }\cos\theta\text{ decreases . }\]

\[ \therefore\text{ Maximum value of }\cos\left[ \cos\left( x \right) \right] = \cos\left( 0 \right) = 1'\]

\[\text{ And, minimum value of }\cos\left[ \cos\left( x \right) \right] = cos\left( 1 \right)\]