Chapter 2

Quadratic Functions

Solving quadratics and using the discriminant to find the number of roots — with an interactive exercise.

Quadratic Functions have the form $ax^2+bx+c$. Solve $ax^2+bx+c=0$ by factorising, completing the square, or the quadratic formula.

The discriminant $b^2-4ac$ tells the number of real roots: positive → 2 roots, zero → 1 root, negative → none. For $x^2-5x+6=0$, the roots are $x=2$ and $x=3$.

Remember

  • Discriminant $=b^2-4ac$.
  • Zero discriminant → one repeated root.

Stuck on this topic? A verified JomKelas tutor can walk you through it.

Find a verified tutor