Platform and version requirements: JVM (1.2), JS (1.2), Native (1.2)

fun acosh(x: Double): Double

fun acosh(x: Float): Float

Computes the inverse hyperbolic cosine of the value x.

The returned value is positive y such that cosh(y) == x.

Special cases:

• acosh(NaN) is NaN
• acosh(x) is NaN when x < 1
• acosh(+Inf) is +Inf