Invalid procedure call or arg

[Philosophaie]

Could someone explain to me what is a:

Invalid procedure call or argument

error in VBA. It is centered around the equation:

If e3 <> 1 Then TA3 = 2 * 180 / Pi * Math.Atn(Math.Sqr((1 + e3) / (1 - e3)) * Math.Tan(EA3 / 2 * Pi / 180))

e3, EA3 exist and Pi=Application.WorksheetFunction.Pi is declared.

 

[Norie]

What's the value of the variable e3 when you get the error?

 

[Norie]

Actually what are the values of both variables, e3 and EA3?