printf("sum is%ld\n",sum);
return 0;
}
4:求一元二次方程的根?
#include<stdio.h>
#include<math.h>
int main()
{
double a,b,c,disc,x1,x2,p,q;
scanf("a=%lfb=%lfc=%lf",&a,&b,&c);
disc=b*b-4*a*c;
p=-b/(2.0*a);
q=sqrt(disc)/(2.0*a);
x1=p+q;x2=p-q;
printf("x1=%7.2f\nx2=%7.2f\n",x1,x2);
return 0;