Sine and cosine approximations

The following expressions can be used to approximate sine and cosine, either in degrees or radians.

Sine

 * sin(x°) ≈ $x⁄90$$90 - x⁄90$ for x > 0 (Degrees)

Cosine

 * cos(x°) ≈ $90 - x⁄90$$x⁄90$ for x > 0 (Degrees)
 * cos(x°) ≈ √(1 - x2) for -1 < x < 1 (Radians)