Next: acosh, Previous: abs, Up: Internal Routines [Contents][Index]

`acos(`

)`x`

Returns the arc cosine of numerical

, in radians. This
function accepts complex arguments.
`x`

For ordinary (real) arguments, the arc cosine is only defined for
arguments between `-1`

and `+1`

(inclusive). Multiply by

to get degrees.
`#rad`

The arc cosine function is defined for any complex argument.

Reverse: cos

See also: asin, atan, #rad, Trigonometry, Complex Functions