Arccos Calculator (Inverse Cosine)
The Arccos function (cos-1) returns the angle whose cosine is a given number. Input must be between -1 and 1.
Common Arccos Values
| x | cos-1(x) in Radians | cos-1(x) in Degrees | cos-1(x) in π Form |
|---|---|---|---|
| -1 | π | 180° | π |
| -0.5 | 2π/3 | 120° | 2π/3 |
| 0 | π/2 | 90° | π/2 |
| 0.5 | π/3 | 60° | π/3 |
| 1 | 0 | 0° | 0 |
| √3/2 | π/6 | 30° | π/6 |
| √2/2 | π/4 | 45° | π/4 |