In this example, you will learn to find the roots of a quadratic equation in C programming

Every quadratic equation gives two values of the unknown variable and these values are called roots of the equation.

A quadratic equation has two roots which may be unequal real numbers or equal real numbers, or numbers which are not real. If a quadratic equation has two real equal roots α, we say the equation has only one real solution.

Example :

` ````
#include <math.h>
#include <stdio.h>
int main() {
double a, b, c, discriminant, root1, root2, realPart, imagPart;
printf("Enter coefficients a, b and c: ");
scanf("%lf %lf %lf", &a, &b, &c);
discriminant = b * b - 4 * a * c;
// condition for real and different roots
if (discriminant > 0) {
root1 = (-b + sqrt(discriminant)) / (2 * a);
root2 = (-b - sqrt(discriminant)) / (2 * a);
printf("root1 = %.2lf and root2 = %.2lf", root1, root2);
}
// condition for real and equal roots
else if (discriminant == 0) {
root1 = root2 = -b / (2 * a);
printf("root1 = root2 = %.2lf;", root1);
}
// if roots are not real
else {
realPart = -b / (2 * a);
imagPart = sqrt(-discriminant) / (2 * a);
printf("root1 = %.2lf+%.2lfi and root2 = %.2f-%.2fi", realPart, imagPart, realPart, imagPart);
}
return 0;
}
```

Output :

` ````
Enter coefficients a, b and c: 10
20
30
root1 = -1.00+1.41i and root2 = -1.00-1.41i
```

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