Nature Of The Roots Of A Quadratic Equation The nature of the roots depends on the value of b2 – 4ac. bx2 – 4ac is called the discriminant of the quadratic equation ax2 + bx + c = 0 and is generally, denoted by D. ∴ D = b2 – 4ac If D > 0, i..e., b2 – 4ac > 0, i.e., b2 – 4ac is positive; the roots are real and unequal. Also, (i) If b2 – 4ac is a perfect square, the … [Read more...] about Nature Of The Roots Of A Quadratic Equation