Completing the square
What Completing the square means in Mathematics A-Level, as defined for AQA, Pearson Edexcel, WJEC.
Definitions of Completing the square
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Reference: Pearson Edexcel
Writing ax² + bx + c as a(x + p)² + q, which gives the minimum or maximum value q at x = −p and the line of symmetry x = −p.
Used in x and in y to convert a general circle equation into centre-radius form, recovering the centre and radius.
A method used to rewrite an expanded circle equation in standard form so the centre and radius can be found.
Rewrites a quadratic expression ax² + bx + c into the canonical form a(x + p)² + q.
Rewriting ax²+bx+c as a(x+p)²+q, which reveals the vertex and enables solution.
Topics that use Completing the square
- B: Algebra and functions (AQA A-Level)
- C: Coordinate geometry in the (x, y) plane (AQA A-Level)
- Algebra and functions (Pearson Edexcel A-Level)
- Coordinate geometry in the (x, y) plane (Pearson Edexcel A-Level)
- Algebra and Functions (AS Unit 1: Pure Mathematics A) (WJEC A-Level)
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Using Completing the square in the exam
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