Acos

Finds the arccosine of an angle

Syntax
	KeyPgDeclareDeclare KeyPgFunctionFunction Acos ( KeyPgByvalByVal number KeyPgAsAs KeyPgDoubleDouble ) KeyPgAsAs KeyPgDoubleDouble

Usage
	result = Acos( number )

Parameters
	number
		A cosine value in the range [-1..1].

Return Value
	The arccosine of number, in radians, in the range [0..Pi].

Description
	Acos returns the arccosine of the argument number as a KeyPgDoubleDouble within the 
	range of 0 to TutMathAnglesPi.  The arccosine is the inverse of the KeyPgCosCos function. The 
	returned angle is measured in TutMathAnglesradians (not TutMathAnglesdegrees).

	Acos can be overloaded as operator to accept user-defined types.

Example
	Dim h As Double
	Dim a As Double
	Input "Please enter the length of the hypotenuse of a triangle: ", h
	Input "Please enter the length of the adjacent side of the triangle: ", a
	Print ""
	Print "The angle between the sides is"; Acos ( a / h )
	Sleep

The output would look like:

	Please enter the length of the hypotenuse of a triangle: 5
	Please enter the length of the adjacent side of the triangle: 4

	The angle between the sides Is 0.6435011087932843

Dialect Differences
	* Not available in the CompilerOptlang-lang qb dialect unless referenced with the 
	  alias __Acos.

Differences from QB
	* New to FreeBASIC

See also
	* KeyPgCosCos
	* TutMathIntroTrigA Brief Introduction To Trigonometry

