#include <stdio.h>
#include <math.h>

int main() { double a=1, b=2, c=3; double discriminant; double x1,x2; printf("a: "); scanf("%lf", &a); printf("b: "); scanf("%lf", &b); printf("c: "); scanf("%lf", &c); discriminant = b * b - 4 * a * c; if (discriminant > 0) { x1 = (-b + sqrt(discriminant)) / (2 * a); x2 = (-b - sqrt(discriminant)) / (2 * a); printf("x1=%.2lf, x2=%.2lf\n", x1, x2); } else { printf("方程没有两个实根\n"); } return 0;
}