Question

Why is the discriminant useful?

Answer 1

To determine how many roots are there in a quadratic equation.

Explanation:

There are 4 natures

`b^2-4ac>0` and is a perfect square -># 2 rational roots

`b^2-4ac>0` and is not a perfect square `->` 2 irrational root
`b^2-4ac=0 ->` 1 root
`b^2-4ac <0` No root