arc-hyperbolic tangent

arc-hyperbolic tangent

[‚ärk ‚hī·pər‚bäl·ik ′tan·jənt]
(mathematics)
For a number, x, with absolute value less than 1, the number whose hyperbolic tangent equals x ; it is the value at x of the inverse of the hyperbolic tangent function. Also known as inverse hyperbolic tangent.