Trigonometry
Radians
● In terms of pi
● Degrees to radians:
π
Degrees V alue × 180°
● Radians to degrees:
180°
Radians V alue × π
● Common Values:
○ 30° = π6 rad
○ 45° = π
4 rad
○ 60° = π
3 rad
○ 90° = π
2 rad
○ 180° = π rad
○ 360° = 2π rad
Trigonometric Graphs in Radians
Sine
● Period of 2π
● Rotational symmetry about origin
● Line of symmetry at θ = π2 and θ = − π
2
Cosine
● Period of 2π
● Line of symmetry in the y-axis
Radians
● In terms of pi
● Degrees to radians:
π
Degrees V alue × 180°
● Radians to degrees:
180°
Radians V alue × π
● Common Values:
○ 30° = π6 rad
○ 45° = π
4 rad
○ 60° = π
3 rad
○ 90° = π
2 rad
○ 180° = π rad
○ 360° = 2π rad
Trigonometric Graphs in Radians
Sine
● Period of 2π
● Rotational symmetry about origin
● Line of symmetry at θ = π2 and θ = − π
2
Cosine
● Period of 2π
● Line of symmetry in the y-axis