acos function
Return the arc cosine of complex
.
There are two branch cuts: One extends right from 1 along
the real axis to ∞, continuous from below. The other extends left from -1
along the real axis to -∞, continuous from above.
Implementation
Complex<num, num> acos(Complex complex) {
var val = complex + Complex(0, 1) * sqrt(Complex(1, 0) - complex * complex);
return log(val) * Complex(0, -1);
}