Find the reference and standard angles

Question

find the trigonometric value.sketch the

angle in standard position, draw in the reference triangle, and label the reference angle.

1. sin 7pi/6

1. tan 3pi/4

1. cos(-10pi/3)

Answer 1

sin(7pi/6) = sin(210) = -1/2

tan(3pi/4) = tan(135) = -1

cos(-10pi/3) = cos(2pi/3) = cos(120) = -1/2

use a calculator with an inverse trig function, if you don't recognize the common reference angles for right triangles with 45-45-90 and 30-60-90 degrees. or pi/4-pi/4-pi/2 and pi/6-pi/3-pi/2 radians and sketch them on a unit circle