19.(C) #Tricky Question--->>>> Finding the roots of ax^2+bx+c

 #include<stdio.h>

#include<math.h>

int main(){

    double a,b,c,x1,x2,discriminant,realpart,imgpart;

    printf("Enter \n a\n b\n c\n");

    scanf("%lf%lf%lf",&a,&b,&c);

    discriminant=b*b-4*a*c;

    if(discriminant>0) // discriminant is used to identify the roots type

    {

       x1=(-b + sqrt(discriminant)) / (2 * a);

       x2=(-b - sqrt(discriminant)) / (2 * a);  /*we have to use

       -,+,*,/ with spaces for getting correct output*/

        printf("ax^2+bx+c solve =%lf and %lf\n",x1,x2);

    }

    else if(discriminant==0)

    {

        x1=x2=-b/(2*a);

        printf("ax^2+bx+c solve = %lf and %lf\n",x1,x2);

    }

    else

    {

        realpart=-b / (2 * a);

        imgpart=(sqrt(-discriminant)) / (2 * a);

        printf("ax^2+bx+c solve =%.2lf+%.2lf i and %.2lf-%.2lf i \n",realpart,imgpart,realpart,imgpart);

    }

    return 0;

}

// this program has teach me so many thing ,thanks mahedi hasan my frnd