This week in Precalc 11 we finished unit 3 with the quadratic equation and interpreting the discriminant.

In lesson 3.4 we learned how to use the quadratic formula : to solve quadratic equations. i found this especially useful with fractions and decimals.

Ex :

In lesson 3.5 we learned how to interpret the discriminant : and how to find whether they are equal roots, real roots, no real roots etc. We also learned how to find the value of a variable when the equation has no real roots, one real root etc.

solutions/real root

solution/equal root

solutions/no real roots

Ex :

determine the value of K when the equation has no real roots: