Chapter 1.6, Problem 30E

To determine

To find: The measure of angle ${\cos }^{-1}\left(0.7\right)$ in radian and degree.

Answer to Problem 30E

Themeasure ofangle in radian is $0.7954$ and degrees is $45.57°$ .

Explanation of Solution

Given information:The given angleis ${\cos }^{-1}\left(0.7\right)$ .

Calculation:

To find the conversion of given angle into radian, use the calculator and enter the keystrokes.

  $\boxed{2\text{nd}}\boxed{\text{COS}}\boxed{0.7}\boxed{)}$

Press $\boxed{\text{MODE}}$ and select the radian mode then quit the window. Now, press $\boxed{\text{ENTER}}$ key.

  ${\cos }^{-1}\left(0.7\right)=0.7954$

To find the conversion of given angle into degree, use the calculator and enter the keystrokes.

  $\boxed{2\text{nd}}\boxed{\text{COS}}\boxed{0.7}\boxed{)}$

Select the degree mode then quit the window. Now, press $\boxed{\text{ENTER}}$ key.

  ${\cos }^{-1}\left(0.7\right)=45.57°$

Therefore, the measure of angle in radian is $0.7954$ and degrees is $45.57°$ .