Coaching Centre
Chapter 8: Quadratic expressions and equations Notes
Factorising quadratics, completing the square, solving quadratic equations by factorising, completing the square and the quadratic formula, the discriminant, and quadratic problems.
Sections
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8A Completing the square Mastered
Factorising review, perfect squares, completing the square for x² + bx, writing quadratics in the form (x + h)² + k, and solving by completing the square.
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8B The quadratic formula Mastered
Solving any quadratic equation ax² + bx + c = 0 with the quadratic formula, exact surd answers and decimal approximations.
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8C The discriminant Mastered
The discriminant Δ = b² − 4ac and how it tells the number and type of solutions of a quadratic equation.
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8D Problems with quadratic equations Mastered
Setting up and solving quadratic equations from area, motion, number and finance problems, and interpreting which solutions make sense.