# *Quadratic equation ax2 + bx + c = 0 (a, b & c ε R with a ≠ 0) b 2 – 4 a c = D (discriminate)

***Quadratic equation**

ax^{2} + bx + c = 0 (a, b & c ε R with a ≠ 0)

b ^{2 }– 4 a c = D (discriminate)

Roots of quadratic are

The following 6 situations may arise.

If D > 0, then roots are real & unequal.

If D < 0, then roots are imaginary & unequal.

If D = 0, then roots are real & equal.

If D > 0 & a perfect square, then roots are rational.

If D > 0 & not a perfect square, then roots are irrational.

If a = 1, b & c are integers, then roots are rational.