# Trigonometry Examples

Find the Reference Angle (10pi)/3
Find an angle that is positive, less than , and coterminal with .
Subtract from .
The resulting angle of is positive, less than , and coterminal with .
Since the angle is in the third quadrant, subtract from .
Simplify the result.
To write as a fraction with a common denominator, multiply by .
Combine fractions.
Combine and .
Combine the numerators over the common denominator.
Simplify the numerator.
Multiply by .
Subtract from .