### Home > APCALC > Chapter 1 > Lesson 1.4.2 > Problem1-158

1-158.

Without using a calculator, determine the exact value of each of the following trig expressions. Homework Help ✎

1. sin($\frac { 5 \pi } { 6 }$)

Visualize the angle on the unit circle. What side ratio correspond with that angle? What quadrant is it in? (This will determine whether your answer will be positive or negative.)

$\frac{1}{2}$

2. cos($\frac { - 3 \pi } { 4 }$)

See hint in part (a).

3. tan($\frac { \pi } { 3 }$)

$\text{Recall that tan}(a)=\frac{\text{sin}(a)}{\text{cos}(a)}$

4. sec($\frac { 5 \pi } { 3 }$)

$\text{Recall that sec}(a)=\frac{1}{\text{cos}(a)}$