Paper 1 · Algebra
⏱ Tested in 3 exam questions since 2020
Lesson 10 of 23
Algebra 10 – Generating a cubic equation given the roots
In this lesson you’ll learn to
- Predict a polynomial's shape from its degree and the sign of its leading term
- Build a cubic in ax³ + bx² + cx + d = 0 form from its three roots
- Spot a double root where the graph's turning point sits on the x-axis
- Fix both the shape and the y-intercept with a single scaling multiplier
Most recent exam questions
- 2024 Paper 1 Q7(c) — construct a cubic from its roots and y-intercept — the three roots fix the linear factor…
- 2022 Paper 1 Q3(a) — reconstruct a quadratic from its roots — either via the factor form (x − r₁)(x − r₂) or…
- 2020 Paper 1 Q1(a)(ii) — sum and product of roots of a quadratic — the page-20 formula relating a quadratic's coe…
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