Answer
$ 1.98$ radians
and
$113.6^{\circ}$
Work Step by Step
We are given that $\cos^{-1} (-0.4)$
In order to get the answer in radians, we need to put the calculator in radians mode.
Then, our result will be: $ 1.98$ radians
In order to get the answer in degrees, we need to put the calculator in degrees mode.
Then, our result will be: $113.6^{\circ}$
