自定义函数求一元二次方程

解题思路:

注意事项:

参考代码:

#include<stdio.h>

#include<math.h>

void d0(double a,double b,double c);

void d1(double a,double b,double c);

void d2(double a,double b,double c);

int main()

{

double a,b,c;

scanf("%lf %lf %lf",&a,&b,&c);

double root=b*b-4*a*c;

if(root>0){

     d0(a,b,c);

}

else if(root==0){

     d1(a,b,c);

}

else if(root<0){

     d2(a,b,c);

}

}

void d0(double a,double b,double c){

    double root=b*b-4*a*c;

    double root1=((-b)+sqrt(root))/(2*a);

    double root2=((-b)-sqrt(root))/(2*a);

   printf("x1=%.3lf x2=%.3lf",root1,root2);

}

void d1(double a,double b,double c){

    double root=-b/(2*a);

    printf("x1=%.3lf ",root);

}

void d2(double a,double b,double c){

    double root=b*b-4*a*c;

    double root1=-b/(2*a);

    double root2=sqrt(-root)/(2*a);

    printf("x1=%.3lf+%.3lfi x2=%.3lf-%.3lfi",root1,root2,root1,root2);

}