DADiSP Worksheet Functions > Function Categories > Trigonometric Functions > ACOSH

 

ACOSH

Purpose:

Calculates the inverse hyperbolic cosine of any expression.

Syntax:

ACOSH(val)

val

-

A scalar, series or table.

Returns:

A scalar, series, or table.

Example:

acosh(1..pi/100..pi);gridhv;griddot

 

 

image\acoshpic01.gif

 

displays the hyperbolic inverse cosine from 1 to π.

Example:

acosh(2)

 

returns 1.3169579.

Example:

acosh(-2..0.1..2)

 

returns a 41 point complex series.

Remarks:

The inverse hyperbolic cosine is defined as:

 

image\acosh01.gif

 

for all complex z. The function is multi-valued and this definition places the branch cut in the complex plane at [-∞, 1].

 

For real x, where x < 0, acosh(x) returns a complex result.

 

SETDEGREE and SETRADIAN have no effect on this function because it always operates in radians.

See Also:

ACOS

ASECH

COS

COSH

GACOSH

TRIGONOMETRIC FUNCTIONS