Trigonometry

[Brian]

I'm a student using MS Access 2000. I don't see an inv or
arc function within the build query expressions box. I
need to use ArcCos (inverse of the cosine). Any ideas?

 

[Sam]

You'll need to use arctan (ATN) to derive arccos.

From Access help...
Arccos(X) = Atn(-X / Sqr(-X * X + 1)) + 2 * Atn(1)

OR if you'll be using ArcCos heaps then write your own simple function
within a module. It will then be avaialble via the expression builder.

Function Acos(X)
Acos = Atn(-X / Sqr(-X * X + 1)) + 2 * Atn(1)
End Function

You'll need to add some error trapping.

HTH
Sam