Paper 1 · Algebra ⏱ Tested in 2 exam questions since 2023 Lesson 20 of 23

Algebra 20 – Pascal’s triangle

In this lesson you’ll learn to

  • Build Pascal's triangle row by row and pick row n + 1 for (x + y)ⁿ
  • Expand (x + y)ⁿ with descending x powers and ascending y powers
  • Alternate the signs when expanding (x − y)ⁿ
  • Simplify terms like 4·(2x)³·(3y), cubing the coefficient with the variable

Most recent exam questions

  • 2025 Paper 1 Q5(a) — binomial expansion at low power — either direct multiplication or the binomial theorem w…
  • 2023 Paper 1 Q1(b) — specific-term extraction from a binomial expansion, with a 1/x term inside the bracket —…
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