Arcsin in VB6 [Resolved]

Hi,

There is no built-in function for Arcsin in VB6.

However, the MSDN Help files state that the following will produce the arcsin

Arcsin(X) = Atn(X / Sqr(-X * X + 1))

I cannot believe this formula is correct (probably my misunderstanding of something) as when x = 1 there is a division by zero error.

Can anyone help please.

When they made VB, they probably just skipped right over those. The Derived Math Functions seem to be an afterthought, and, as such, they don't really work perfectly. As in the other thread, you should probably just use If to make it work properly. If you really felt ambitious, you could look up the actual series and implement that :).

Hi,

If anyone is interested the following is the answer

VB Code:

Z = Sqr(-X * X + 1)
    If Abs(Z) <> 0 Then
        Tot1 = Atn(X / Z)
    Else
        Tot1 = pi/ 2
    End If