Paper 1 · Algebra
⏱ Tested in 4 exam questions since 2017
Lesson 9 of 23
Algebra 9 – Nature of quadratic graphs
You’ll learn
- Compute the discriminant b² − 4ac and link its sign to the nature of the roots
- Match exam wording — distinct, equal, real, no real — to >, =, ≥, <
- Turn a nature-of-roots condition into an equation or inequality in k or t
- Finish discriminant conditions with a t² term using the parabola-sketch method
Formula used
Roots of the quadratic equation
x = (-b ± √(b² − 4ac)) / 2a
On page 20 of the log tables — read it off, don’t memorise.Most recent exam questions
- 2025 P1 Q6(b)(i)
- 2022 P1 Q1(a)
- 2022 P1 Q1(b)
- 2020 P1 Q1(a)(iii)
- 2017 P1 Q1(c)(i)
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