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#include "__invtrigl.h"

#if LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384

static const long double
pS0 =  1.66666666666666666631e-01L,
pS1 = -4.16313987993683104320e-01L,
pS2 =  3.69068046323246813704e-01L,
pS3 = -1.36213932016738603108e-01L,
pS4 =  1.78324189708471965733e-02L,
pS5 = -2.19216428382605211588e-04L,
pS6 = -7.10526623669075243183e-06L,
qS1 = -2.94788392796209867269e+00L,
qS2 =  3.27309890266528636716e+00L,
qS3 = -1.68285799854822427013e+00L,
qS4 =  3.90699412641738801874e-01L,
qS5 = -3.14365703596053263322e-02L;

const long double pio2_hi = 1.57079632679489661926L;
const long double pio2_lo = -2.50827880633416601173e-20L;

/* used in asinl() and acosl() */
/* R(x^2) is a rational approximation of (asin(x)-x)/x^3 with Remez algorithm */
long double __invtrigl_R(long double z)
{
	long double p, q;
	p = z*(pS0+z*(pS1+z*(pS2+z*(pS3+z*(pS4+z*(pS5+z*pS6))))));
	q = 1.0+z*(qS1+z*(qS2+z*(qS3+z*(qS4+z*qS5))));
	return p/q;
}
#endif