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Maths — Pure 1

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Maths — Pure 1

Every note, question and flashcard is written against the official specification and checked before it ships — anything not ready yet is marked as coming soon. How content is checked

SyllabAI Hub — revision for Edexcel IGCSE & IAL and Cambridge International qualifications.

Home/A-Level/Mathematics/Underground Mathematics/Line crossings

Line crossings

Go and think about it...Developingbeyond the specification map

Beyond the specification map. Combinatorial line-arrangement reasoning (C(n,2) context only) — no binomial expansion or AP/GP formula work. It is kept in the library for extra maths practice, not as specification-point coverage.

© University of Cambridge (Underground Mathematics); © UCLES / Oxford MAT / NRICH for sourced exam questions. Source: undergroundmathematics.org.

Line crossings

Excerpt: How many intersections can you have between $n$ straight lines? A deceptively simple question which requires careful reasoning and logic.