Lines Matching refs:acos
30 /* acos(x)
33 * acos(x) = pi/2 - asin(x)
34 * acos(-x) = pi/2 + asin(x)
36 * acos(x) = pi/2 - (x + x*x^2*R(x^2)) (see asin.c)
38 * acos(x) = pi/2 - (pi/2 - 2asin(sqrt((1-x)/2)))
45 * acos(x) = pi - 2asin(sqrt((1-|x|)/2))
71 acos (double x)
82 if (hx > 0) /* acos(1) = 0 */
86 else /* acos(-1) = pi */
91 return NAN; /* acos(|x|>1) is NaN */
129 } /* acos */