EXAMPLE 2
Solve a trigonometric equation
STEP 2
Find the angle in Quadrant III (where
180° <
θ
< 270°
) that has the same sine
value as the angle in Step 1. The angle is:
θ
180
° +
38.7
° =
218.7
°
CHECK :
Use a calculator to check the answer.
5
8
sin 218.7
°
–
0.625
=
–
P