第1个回答 2013-11-27
#include <stdio.h>
#include <math.h>
int main()
{
double a,b,c,disc,x1,x2,realpart,imagpart;
scanf("%lf%lf%lf",&a,&b,&c);
printf("The equation");
if (fabs(a)<=1e-6)
printf(" is not a quadratic\n");
else
{
disc=b*b-4*a*c;
if (fabs(disc)<=1e-6)
printf(" has two equal roots:%8.4f\n",-b/(2*a));
else
if (disc>0)
{
x1=(-b+sqrt(disc))/(2*a);
x2=(-b-sqrt(disc))/(2*a);
printf(" has distinct real roots:%8.4f and %8.4f\n",x1,x2);
}
else
{
realpart=-b/(2*a);
imagpart=sqrt(-disc)/(2*a);
printf(" has complex roots:\n");
printf("%8.4f+%8.4fi\n",realpart,imagpart);
printf("%8.4f-%8.4fi\n",realpart,imagpart);
}
}
return 0;
}
第2个回答 2013-11-27
#include "stdio.h"
#include "math.h"
double x1,x2,p;
float file1(float a,float b)
{
x1=(-b+sqrt(p))/2*a;
x2=(-b-sqrt(p))/2*a;
return 0;
}
float file2(float a,float b)
{
x1=x2=(-b+sqrt(p))/2*a;
return 0;
}
void main()
{
float a,b,c;
scanf("%f%f%f",&a,&b,&c);
p=b*b-4*a*c;
printf("方程是:%.3f*x*x+%.3f*x+%.3f=0\n",a,b,c);
if(p>0)
{
file1(a,b);
printf("X1=%f\tX2=%f\n",x1,x2);
}
else if(p==0)
{
file2(a,b);
printf("X1=%f\tX2=%f\n",x1,x2);
}
else printf("方程无解");
}
运行正确 输入: 2 3.7 1.2
输出 X1=-1.677625 X2=-5.722375本回答被网友采纳
第3个回答 2020-10-18
#include<stdio.h>
#include<math.h>
int main(void)
{
float a,b,c;
double x1,x2;
double delta;
printf("输入a,b,c数值:\n");
scanf("%f%f%f",&a,&b,&c);
if (a!=0)
{delta=pow(b,2)-4*a*c;
if(delta==0){
printf("x1=x2=%.2f\n",-b/(2*a));}
if(delta>0) {
x1=(-b+sqrt(delta))/(2*a);
x2=(-b-sqrt(delta))/(2*a);
printf("x1=%.2f x2=%.2f\n",x1,x2);}
if(delta<0) {
printf("无解!\n");}
}
return 0 ;
}