PreCalc 2 · Trigonometric Functions
Write a fraction. Put π radians over 180° so the degrees cancel. Multiply straight across, then reduce.
The conversion
1 full turn is 360° and also 2π radians. That gives the factor
π rad180°
Always put degrees on the bottom so they cancel.
Worked conversion
Convert 150°.
150°1×π rad180°
The degree symbols cancel. Multiply straight across:
150π180 = 5π6
Convert 150° to radians.
150°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
150π180 = 5π6
Answer: 5π6
Convert 30° to radians.
30°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
30π180 = π6
Answer: π6
Convert 45° to radians.
45°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
45π180 = π4
Answer: π4
Convert 90° to radians.
90°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
90π180 = π2
Answer: π2
Convert 180° to radians.
180°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
180π180 = π
Answer: π
Convert 360° to radians.
360°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
360π180 = 2π
Answer: 2π
Convert 15° to radians.
15°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
15π180 = π12
Answer: π12
Convert 60° to radians.
60°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
60π180 = π3
Answer: π3
Convert 120° to radians.
120°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
120π180 = 2π3
Answer: 2π3
Convert 135° to radians.
135°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
135π180 = 3π4
Answer: 3π4
Convert 240° to radians.
240°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
240π180 = 4π3
Answer: 4π3
Convert 300° to radians.
300°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
300π180 = 5π3
Answer: 5π3
Convert 315° to radians.
315°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
315π180 = 7π4
Answer: 7π4
Convert 330° to radians.
330°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
330π180 = 11π6
Answer: 11π6
Convert 250° to radians.
250°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
250π180 = 25π18
Answer: 25π18
Convert 21° to radians.
21°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
21π180 = 7π60
Answer: 7π60
Convert 33° to radians.
33°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
33π180 = 11π60
Answer: 11π60
Convert 78° to radians.
78°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
78π180 = 13π30
Answer: 13π30
Convert 7° to radians.
7°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across. Nothing cancels.
The answer is 7π180.
Answer: 7π180
Convert −13° to radians.
−13°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across. Nothing cancels.
The answer is −13π180.
Answer: −13π180
Convert 450° to radians.
450°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
450π180 = 5π2
Answer: 5π2
Convert 76° to radians.
76°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
76π180 = 19π45
Answer: 19π45
Convert −150° to radians.
−150°1×π rad180°
Degrees go on the bottom of the conversion so the degrees cancel.
Multiply straight across, then reduce.
−150π180 = −5π6
Answer: −5π6
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