✔ Appearance ✔ Standard ✔ Console
radianAngle# = ACOS (expr)
Returns the arccosine of
expr in radians. In other words, if
expr represents the cosine of some angle, then
ACOS(expr) returns the angle. The returned angle will be in the range of 0 to π radians (which corresponds to 0 to 180 degrees).
ACOS always returns a double-precision result.
No special notes.