How do you find the reference angle of theta=-245^circ and sketch the angle in standard position?
1 Answer
Apr 26, 2018
The reference angle is 65°.
Explanation:
Assuming an angle is in standard position, its reference angle is the smallest angle you can make between the terminal ray and the whole left-right
Mathematically, the reference angle is the difference between the angle and the closest multiple of 180°.
theta_"ref" = min{abs(theta-180n°):n in ZZ}
An angle of
Thus, the closest multiple of 180° to
The difference between these two is
abs(–245° - (–180°))
=abs(–245°+180°)
=abs(–65°)
=65°
Visual shortcut:
Draw the angle
