/* Bai tap 4_1 - Giai phuong trinh bac hai AXý + BX + C = 0 */

#include <stdio.h>

#include <math.h>

int main()

{

float a, b, c, delta;

printf("

Giai phuong trinh bac hai AXý + BX + C = 0");

printf("

Cho biet ba he so A B C : ");

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

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

if (delta<0)

printf("Phuong trinh vo nghiem");

else if (delta == 0)

printf("Phuong trinh co nghiem kep x1 = x2 = %f", -b/(2*a));

else

{

printf("Phuong trinh co hai nghiem phan biet

x1 = %f", (-b + sqrt(delta))/(2*a));

printf("

x2 = %f", (-b - sqrt(delta))/(2*a));

}

getchar();

}