PreCalc 2 · Trigonometric Functions
Write a fraction. Put 180° over π radians so the radians cancel. Multiply straight across, then reduce.
The conversion
1 full turn is 2π radians and also 360°. That gives the factor
180°π radians
Always put radians on the bottom so they cancel.
Worked conversion
Convert π3.
π 3×180°π
The radians cancel, and the π cancels too. Multiply straight across:
180°3 = 60°
Convert π3 to degrees.
π 3×180°π
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across, then reduce.
180°3 = 60°
Answer: 60°
Convert π6 to degrees.
π radians6×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across, then reduce.
180°6 = 30°
Answer: 30°
Convert π4 to degrees.
π radians4×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across, then reduce.
180°4 = 45°
Answer: 45°
Convert π2 to degrees.
π radians2×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across, then reduce.
180°2 = 90°
Answer: 90°
Convert π to degrees.
π radians1×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across.
180°
Answer: 180°
Convert 2π to degrees.
2π radians1×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across.
2 · 180° = 360°
Answer: 360°
Convert π8 to degrees.
π radians8×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across, then reduce.
180°8 = 45°2 = 22.5°
Answer: 22.5°
Convert 2π3 to degrees.
2π 3×180°π
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across, then reduce.
360°3 = 120°
Answer: 120°
Convert 3π4 to degrees.
3π radians4×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across, then reduce.
540°4 = 135°
Answer: 135°
Convert 5π6 to degrees.
5π radians6×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across, then reduce.
900°6 = 150°
Answer: 150°
Convert 5π3 to degrees.
5π radians3×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across, then reduce.
900°3 = 300°
Answer: 300°
Convert 7π4 to degrees.
7π radians4×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across, then reduce.
1260°4 = 315°
Answer: 315°
Convert 4π3 to degrees.
4π radians3×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across, then reduce.
720°3 = 240°
Answer: 240°
Convert 13π10 to degrees.
13π radians10×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across, then reduce.
2340°10 = 234°
Answer: 234°
Convert −3π to degrees.
−3π radians1×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across.
−3 · 180° = -540°
Answer: -540°
Convert 11π6 to degrees.
11π 6×180°π
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across, then reduce.
1980°6 = 330°
Answer: 330°
Convert 4 radians to degrees. Round to 2 decimal places.
4 1×180°π
Radians go on the bottom of the conversion so the radians cancel.
There is no π on top to cancel, so π stays in the denominator.
Use a calculator.
720°π ≈ 229.1831... → 229.18°.
Answer: 229.18°
Convert −π2 to degrees.
−π radians2×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across, then reduce.
−180°2 = -90°
Answer: -90°
Convert 5π2 to degrees.
5π radians2×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across, then reduce.
900°2 = 450°
Answer: 450°
Convert π12 to degrees.
π radians12×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across, then reduce.
180°12 = 15°
Answer: 15°
Convert 7π6 to degrees.
7π radians6×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across, then reduce.
1260°6 = 210°
Answer: 210°
Convert 3π2 to degrees.
3π radians2×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across, then reduce.
540°2 = 270°
Answer: 270°
Convert π17 to degrees.
π radians17×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
The π factors cancel too.
Multiply straight across. This does not reduce to a nice number, so use a calculator.
180°17 ≈ 10.59°.
Answer: 10.59°
Convert 2 radians to degrees. Round to 2 decimal places.
2 radians1×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
There is no π on top to cancel, so π stays in the denominator.
Use a calculator.
360°π ≈ 114.5916... → 114.59°.
Answer: 114.59°
Convert 1 radian to degrees. Round to 2 decimal places.
1 radians1×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
There is no π on top to cancel, so π stays in the denominator.
Use a calculator.
180°π ≈ 57.2958... → 57.30°.
Answer: 57.30°
Convert 3 radians to degrees. Round to 2 decimal places.
3 radians1×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
There is no π on top to cancel, so π stays in the denominator.
Use a calculator.
540°π ≈ 171.8873... → 171.89°.
Answer: 171.89°
Convert 0.5 radians to degrees. Round to 2 decimal places.
0.5 radians1×180°π radians
Radians go on the bottom of the conversion so the radians cancel.
There is no π on top to cancel, so π stays in the denominator.
Use a calculator.
90°π ≈ 28.6479... → 28.65°.
Answer: 28.65°
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