### Home > INT3 > Chapter Ch9 > Lesson 9.1.6 > Problem9-77

9-77.
1. Calculate the value of each expression. Give an exact answer, if possible. Each angle measure is given in radians. Homework Help ✎

1. sin(4)

2. sin

$\text{Since }\frac{4\pi}{3} \text{ is related to the }30\degree-60\degree-90\degree\text{ angles, this one}$
$\text{has an exact answer. Locate it on the unit circle.}$
$\text{Notice that it will be a reflection (twice) of sin} \left(\frac{\pi}{3}\right).$