basic trigonometry in GDL for the mathematically challenged

[David Collins]

I'm trying to get GDL to come up with the adjacent angle of a right triangle for which I know the base and the hypotenuse.
SINa = Opposite/Hypotenuse. Cool.
How do I solve for "a"? All my old books assume I'm going to go look it up in the tables. Is there a way to get GDL to hand over the angle if I know the value of SINa?
I note with great interest that sin a = +/- SQR( 1-cos**a). Oh, my head!

[Anonymous]

Try the ASN fonction.
The syntaxe is
a = ASN (opposite/hypothenuse)
the value of "a" will be in this "area" : -90° < ASN(x) < 90°

[David Collins]

That did the trick!
Many thanks.