Algebra and functions
Completing the square and the vertex
Rewrite as , read off the vertex, line of symmetry and least or greatest value, and use it to sketch parabolas and solve real problems about maximum height or area.
≈ 45 minSolving quadratic equations
Three ways to solve (factorising, completing the square and the formula), choosing the quickest, giving exact answers, and spotting quadratics in disguise such as .
≈ 45 minThe discriminant and the nature of roots
How tells you whether a quadratic has two, one or no real roots without solving it, how to find unknown constants from that, and how to show an expression is always positive.
≈ 40 minLinear and quadratic inequalities
Solve linear inequalities, then quadratic ones using critical values and a sketch, write the answer correctly (and, or, set notation), and combine two conditions.
≈ 35 minSimultaneous equations and lines meeting curves
Solve one linear and one quadratic equation together by substitution, find the points where a line meets a curve, and use the discriminant to decide whether a line crosses, touches or misses a curve.
≈ 40 minIndices and surds
means "take the th root, then raise to the power ", and . Surds are roots left exact: simplify them by pulling out square factors, and remove them from denominators by multiplying by the conjugate.
≈ 30 minPolynomials: division, factor and remainder theorems
Long division for polynomials, why the remainder on dividing by is just , and how the factor theorem lets you factorise cubics and find unknown coefficients.
≈ 45 minPartial fractions
Splitting a complicated fraction into simpler ones, which you need for integrating and for binomial expansions: the right form for each kind of denominator, and quick ways to find the constants.
≈ 45 minModulus graphs and equations
What means, how to sketch by reflecting the negative part, and two reliable ways to solve modulus equations: squaring both sides, or splitting into cases and checking.
≈ 40 minModulus inequalities
Solving inequalities with moduli: the "between" and "outside" patterns, squaring when both sides are moduli, and using a sketch when a modulus is compared with a line.
≈ 40 minCurve sketching and transformations
A factorised cubic crosses the -axis at each factor's root and touches it at a repeated root. Reciprocal graphs have asymptotes. Changes outside the bracket act vertically and do what you expect; changes inside act horizontally and do the opposite.
≈ 40 minFunctions, domain and range
What makes a rule a function, function notation, the largest possible domain, and how to find the range of linear and quadratic functions on any domain.
≈ 40 minComposite functions
Applying one function after another: what means, finding and solving with composite expressions, and when a composite function exists.
≈ 35 minOne-one and inverse functions
Which functions can be undone, how to find , why the domain of the inverse is the range of the function, and how to invert a quadratic on a restricted domain.
≈ 45 minGraphs of a function and its inverse
Why the graph of is the reflection of in the line , how points, intercepts and asymptotes swap over, and where a function meets its own inverse.
≈ 30 minTransformations of graphs
Translating, stretching and reflecting : what each of , , and does, how to describe it in exam language, and how to combine transformations in the right order.
≈ 50 min