Question

Question #190b0

Answer 1

`1.23095942 rad=70.5287794°`

Explanation:

For values not on the unit circle, it's easiest to use a calculator.

Take the inverse cosine of both sides to "undo" the cosine function.

`costheta=(1/3)`
`cos^-1(costheta)=cos^-1(1/3)`
`theta=cos^-1(1/3)`

`theta=1.23095942 rad=70.5287794°`

[can be expressed in radians or degrees]