Ach

This function returns the inverse hyperbolic cosine of a specified number.

Syntax

ach(number)

Examples

RESULT=ach(2) : # 1.3169579

Comments

For real positive numbers, the hyperbolic cosine definition is as follows:

ach(x)=ln(x+sqr(x^2-1))

The type of result is Double.

Associated errors

See also

ash, ath, ch, sh,th, ln, sqr.