| Concept | Description | Example |
|---|---|---|
| Quadratic Form | ax² + bx + c (where a ≠ 0) | 3x² + 5x + 2 |
| Factorised Form | (px + q)(rx + s) | (x + 1)(x + 2) |
| Key Pattern | (x + a)(x + b) = x² + (a + b)x + ab | (x + 3)(x + 4) = x² + 7x + 12 |
| Perfect Square | (x + a)² = x² + 2ax + a² | (x + 5)² = x² + 10x + 25 |
| Difference of Squares | (x + a)(x - a) = x² - a² | (x + 3)(x - 3) = x² - 9 |
This key facts covers Key Facts About Quadratic Expressions within Quadratic Expressions for GCSE Mathematics. Revise Quadratic Expressions in Algebra for GCSE Mathematics with 12 exam-style questions and 22 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 2 of 8 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.
Practice questions for Quadratic Expressions
Expand (x + 5)².
Explain how to recognise whether x² + 12x + 36 is a perfect square trinomial, and write it in factorised form.
Quick recall flashcards
Expand (x + 6)(x - 4)
x² - 4x + 6x - 24
= x² + 2x - 24
(Be careful with negative signs!)
Expand (x + 2)(x + 5)
x² + 5x + 2x + 10
= x² + 7x + 10
(Using FOIL: First + Outer + Inner + Last)