The following functions are built into VB.Net
Math.SinH Math.CosH and Math.TanH

Public Function SecH(x As Double) As Double
 Return 1 / Math.Cosh(x)
End Function
'
Public Function CosecH(x As Double) As Double
 Return 1 / Math.Sinh(x)
End Function
'
Public Function CotH(x As Double) As Double
 Return 1 / Math.Tanh(x)
End Function
  

The following functions are built into VB.Net
Math.ASinH Math.ACosH and Math.ATanH

Public Function ASecH(x As Double) As Double
 Return Math.Acosh(1 / x)
End Function
'
Public Function ACosecH(x As Double) As Double
 Return Math.Asinh(1 / x)
End Function
'
Public Function ACotH(x As Double) As Double
 Return Math.Atanh(1 / x)
End Function
  

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