Arccos(x) Calculator — inverse cosine function

How to use the arccos(x) calculator
1. Enter a real number \(x\) that belongs to the domain \([-1 , 1]\) and choose the number of decimal places.
2. Press calculate arccos(x). The answer is displayed in radians and degrees.

Formulas used:
\[ \text{arccos}(x) = y, \quad \cos(y) = x,\quad y \in [0,\pi] \]
\[ \text{degrees} = \text{radians} \times \frac{180}{\pi} \]

• Domain: \(-1 \le x \le 1\)    (otherwise "x out of domain")
• Range: \(0 \le \text{arccos}(x) \le \pi\) radians   ( \(0^\circ\) to \(180^\circ\) )

Example: \(\arccos(0) = \pi/2 \approx 1.571\) rad ( \(90^\circ\) )