Answer
$\color{blue}{\cos{0.8} \approx 0.7}$
Work Step by Step
To approximate the value of $\cos{0.8}$, look for the y-value of the point where the terminal side o the angle 0.8 radian crosses the unit circle.
Notice that for the given angle, the y-value of the point described above is around $0.7$.
Thus,
$\color{blue}{\cos{0.8} \approx 0.7}$
