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arcsin

Function arcsin - the inverse trigonometric function

Calling Sequence  arcsin(x)
Parameters
NameTypeDescription

x numerica numerical value, |x| <= 1
Return Type  numeric
Synopsis This function computes the inverse of the trigonometric sine function. For all -1 <= x <= 1, sin(arcsin(x))=x. For all -Pi/2 <= y <= Pi/2, arcsin(sin(y))=y. The value returned by arcsin is a principal value, it is between (-Pi/2 and Pi/2).
References Handbook of Mathematical Functions, M. Abramowitz and I. Stegun, Ch 4.4
Examples
> arcsin(0);
0
> arcsin(1/2);
0.5236
> arcsin(1);
1.5708
> arcsin(-1);
-1.5708
See also arctan,   cos,   sin,   tan