C语言程序设计教程（第三版）课后习题8.2 （C语言代码）

解题思路:





注意事项:





参考代码:

#include <stdio.h>

#include <math.h>

int main()

{

float a,b,c,d,x1,x2;

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

d=b*b-4*a*c;

if(d>0.000001)

{

x1=(-b+sqrt(d))/(2.0*a);

x2=(-b-sqrt(d))/(2.0*a);

printf("x1=%.3f+%.3fi x2=%.3f-%.3fi\n",x1,0.0,x2,0.0);

}

else if(d>-0.000001)

{

x1=(-b)/(2.0*a);

x2=(-b)/(2.0*a);

printf("x1=%.3f+%.3fi x2=%.3f-%.3fi\n",x1,0.0,x2,0.0);

}

else

{

x1=(-b)/(2.0*a);

x2=(sqrt(-d))/(2.0*a);

printf("x1=%.3f+%.3fi x2=%.3f-%.3fi\n",x1,x2,x1,x2);

}

return 0;

}