Discriminant in Quadratic Formula

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Taught by YourMathGal
  • Currently 4.0/5 Stars.
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Lesson Description:

Defines the discriminant and how to use it to find what types of solutions a quadratic equation has.

More free YouTube videos by Julie Harland are organized at http://yourmathgal.com

Questions answered by this video:
  • What is the discriminant in the quadratic formula?
  • What happens if the discriminant, or b^2 - 4ac, is > 0?
  • What happens if the discriminant, or b^2 - 4ac, is < 0?
  • What happens if the discriminant, or b^2 - 4ac, equals 0?
  • When do you get two real solutions when solving a quadratic equation using the quadratic formula?
  • When do you get two complex or imaginary solutions when solving a quadratic equation using the quadratic formula?
  • When do you get only one solution when solving a quadratic equation using the quadratic formula?
  • What are complex conjugates?
  • How can you use the discriminant to determine the number and types of solutions of 2x^2 - 3x + 4 = 0?
  • How can you use the discriminant to determine the number and types of solutions of 4x^2 - 12x = -9?
  • How can you use the discriminant to determine the number and types of solutions of 8m^2 - 2m - 7 = 0?
  • What happens if the discriminant, or b^2 - 4ac, is a perfect square?
  • Staff Review

    • Currently 4.0/5 Stars.
    This lesson explains the three scenarios that can occur when solving a quadratic equation -- you can get 2 real solutions, 1 real solution, or 2 complex solutions. You can determine which of these will occur based on the discriminant of the quadratic equation, b^2 - 4ac. This is a great synopsis of the different things that can happen when solving a quadratic equation.