Discriminant
What Discriminant means in Mathematics A-Level, as defined for AQA, Pearson Edexcel, WJEC.
Definitions of Discriminant
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Reference: AQA
The value b²−4ac, which determines the number of real roots: positive gives two distinct real roots, zero gives one repeated root, negative gives no real roots.
The value b² − 4ac of a quadratic function, whose sign decides whether the roots are two distinct real roots, a repeated real root or no real roots.
The value Δ = b² − 4ac, which appears under the radical in the quadratic formula and determines the nature of the roots.
Topics that use Discriminant
- B: Algebra and functions (AQA A-Level)
- Algebra and functions (Pearson Edexcel A-Level)
- Algebra and Functions (AS Unit 1: Pure Mathematics A) (WJEC A-Level)
Related terms
- Completing the square
- Factor theorem
- Asymptote
- Asymptotes
- Composite function
- Conjugate
- critical values
- direct proportion
Using Discriminant in the exam
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