The post was too big, I had to split it to maintain readability.
Trig Functions:
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Name: Hyperbolic Sine
VB Code:
Private Function Sinh(ByVal dblNumber As Double) As Double
Sinh = (Exp(dblNumber) - Exp(dblNumber * -1)) / 2
End Function
Example: Sinh(0.707) ' ~ 0.767388542
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Name: Hyperbolic Cosine
VB Code:
Private Function Cosh(ByVal dblNumber As Double) As Double
Cosh = (Exp((dblNumber) + Exp((dblNumber * -1)) / 2
End Function
Example: Cosh(0.707) ' ~ 1.260509887
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Name: Hyperbolic Tangent
VB Code:
Private Function Tanh(ByVal dblNumber As Double) As Double
Tanh = ((Exp(dblNumber) - Exp(dblNumber * -1)) / 2) / ((Exp(dblNumber) + Exp(dblNumber * -1)) / 2)
End Function
Example: Tanh(0.707) ' ~ 0.608792164
-----------------------------------------------------------------------------
Name: Cotangent of an angle
VB Code:
Private Function Cot(ByVal dblRadians As Double) As Double
Cot = (1 / Tan(dblRadians))
End Function
Example: None
-----------------------------------------------------------------------------
Name: Secant of an angle
VB Code:
Private Function Sec(ByVal dblRadiansAs Double) As Double
Sec = (1 / Cos(dblRadians))
End Function
Example: None
-----------------------------------------------------------------------------
Name: Cosecant of an angle
VB Code:
Private Function Csc(ByVal dblRadians As Double) As Double
Csc = 1 / Sin(dblRadians)
End Function
Example: None
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Some New Ones, Added 25-05-05 8:40PM
-----------------------------------------------------------------------------
Name: Arc sine
VB Code:
Private Function ASin(ByVal dblNumber As Double) As Double
If Abs(value) <> 1 Then
ASin = Atn(dblNumber / Sqr(1 - dblNumber * dblNumber))
Else
ASin = 1.5707963267949 * Sgn(dblNumber)
End If
End Function
Example: None
-----------------------------------------------------------------------------
Name: Arc cosine
VB Code:
Private Function ACos(ByVal dblNumber As Double) As Double
If Abs(dblNumber) <> 1 Then
ACos = 1.5707963267949 - Atn(dblNumber / Sqr(1 - dblNumber * dblNumber))
ElseIf number = -1 Then
ACos = 3.14159265358979
End If
End Function
Example: None
-----------------------------------------------------------------------------
Name: Arc cotangent
VB Code:
Private Function ACot(ByVal dblNumber As Double) As Double
ACot = Atn(1 / dblNumber)
End Function
Example: None
-----------------------------------------------------------------------------
Name: Arc secant
VB Code:
Private Function ASec(ByVal dblNumber As Double) As Double
If Abs(value) <> 1 Then
ASec = 1.5707963267949 - Atn((1 / dblNumber / Sqr(1 - 1 / (dblNumber * dblNumber)))
Else
ASec = 3.14159265358979 * Sgn(dblNumber)
End If
End Function
Example: None
-----------------------------------------------------------------------------
Name: Arc cosecant
VB Code:
Private Function ACsc(ByVal dblNumber As Double) As Double
If Abs(dblNumber) <> 1 Then
ACsc = Atn((1 / dblNumber) / Sqr(1 - 1 / (dblNumber * dblNumber)))
Else
ACsc = 1.5707963267949 * Sgn(dblNumber)
End If
End Function
Example: None
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Edit: OOPs, forgot my ByVal's 
Cheers,
RyanJ