In this lesson, we explore the discriminant of a quadratic equation and how its value determines the nature of roots. This is a core CBSE Class 10 Maths topic from Chapter 4 (Quadratic Equations). You'll see animated step-by-step explanations, real NCERT examples, and solved board exam questions.
A quadratic equation where a ≠ 0 and a, b, c are real numbers.
Always gives the roots. Use when factorization is not obvious.
D > 0 → 2 real roots
D = 0 → equal roots
D < 0 → no real roots
α and β are the two roots. Useful for relationship-based questions.
In CBSE board exams, questions on discriminant are almost always 2–3 marks. Always state the value of D clearly and then conclude nature of roots in a separate line to get full marks.
Find the discriminant of 3x² − 5x + 2 = 0 and determine the nature of its roots.
Really helpful explanation! I always confused D=0 with D<0. The animation made it super clear. Thank you! 🙏
Sir can you explain why when D<0 we say "no real roots" — do the roots still exist just as complex numbers?
Everything you need to know