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#include <u.h>#include <libc.h> /* * sinh(arg) returns the hyperbolic sine of its floating- * point argument. * * The exponential function is called for arguments * greater in magnitude than 0.5. * * A series is used for arguments smaller in magnitude than 0.5. * The coefficients are #2029 from Hart & Cheney. (20.36D) * * cosh(arg) is computed from the exponential function for * all arguments. */ static	double	p0  = -0.6307673640497716991184787251e+6;static	double	p1  = -0.8991272022039509355398013511e+5;static	double	p2  = -0.2894211355989563807284660366e+4;static	double	p3  = -0.2630563213397497062819489e+2;static	double	q0  = -0.6307673640497716991212077277e+6;static	double	q1   = 0.1521517378790019070696485176e+5;static	double	q2  = -0.173678953558233699533450911e+3; doublesinh(double arg){	double temp, argsq;	int sign; 	sign = 0;	if(arg < 0) {		arg = -arg;		sign++;	}	if(arg > 21) {		temp = exp(arg)/2;		goto out;	}	if(arg > 0.5) {		temp = (exp(arg) - exp(-arg))/2;		goto out;	}	argsq = arg*arg;	temp = (((p3*argsq+p2)*argsq+p1)*argsq+p0)*arg;	temp /= (((argsq+q2)*argsq+q1)*argsq+q0);out:	if(sign)		temp = -temp;	return temp;} doublecosh(double arg){	if(arg < 0)		arg = - arg;	if(arg > 21)		return exp(arg)/2;	return (exp(arg) + exp(-arg))/2;}