Topics
Using the discriminant Δ=b2−4ac to determine the number of real roots, solving quadratic inequalities from the roots and parabola shape, and applying quadratics to optimization problems.
The discriminant of a quadratic is the term under the square root in the quadratic formula:
When Δ<0, the square root has a negative value inside, and so the quadratic has no real solutions.
When Δ=0, the square root is zero, and the ±√Δ makes no difference, so there is only one real solution.
When Δ>0, √Δ is positive and so ±√Δ yields two real roots.
A quadratic inequality is an inequality of the form
They can be solved by finding the roots of the quadratic and the concavity of the parabola.
Nice work completing Applications of Quadratics, here's a quick recap of what we covered:
Exercises checked off
Using the discriminant Δ=b2−4ac to determine the number of real roots, solving quadratic inequalities from the roots and parabola shape, and applying quadratics to optimization problems.
The discriminant of a quadratic is the term under the square root in the quadratic formula:
When Δ<0, the square root has a negative value inside, and so the quadratic has no real solutions.
When Δ=0, the square root is zero, and the ±√Δ makes no difference, so there is only one real solution.
When Δ>0, √Δ is positive and so ±√Δ yields two real roots.
A quadratic inequality is an inequality of the form
They can be solved by finding the roots of the quadratic and the concavity of the parabola.
Nice work completing Applications of Quadratics, here's a quick recap of what we covered:
Exercises checked off