One of the things we learned this week in Precalc 11 is how to determine how many root(s) a quadratic equation has by figuring out the value of the discriminant.
If the value of the discriminant is <0 then there are no real roots, if >0 then there are two real roots, if =0 then there are 1 real root. By figuring out the discriminant, we can also determine the nature of the root.
Nature of the root
- Real roots – d>0
- No real roots- d<0
- Distinct roots – d>0
- Equal roots – d=0
- Rational roots – d=perfect squares
- Irrational roots – d=not perfect squares
The discriminant is what’s under the square root sign in the quadratic equation
Examples
