How Iteration Works

Part of Iteration · Section 2 of 4

Deep DiveUnit: AlgebraGCSE

This deep dive covers How Iteration Works within Iteration for GCSE Mathematics. Revise Iteration in Algebra for GCSE Mathematics with 9 exam-style questions and 3 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 2 of 4 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.

How Iteration Works

1 Start with an initial value x₀
2 Substitute into the iterative formula to find x₁
3 Use x₁ to find x₂, then x₂ to find x₃, etc.
4 Stop when values converge (become very similar)

Practice questions for Iteration

What is the purpose of using an iterative formula in mathematics?

  • A. To find exact algebraic solutions to equations
  • B. To get increasingly accurate numerical approximations to solutions
  • C. To factorise quadratic expressions
  • D. To draw graphs of functions
1 markfoundation

A student uses the iterative formula xₙ₊₁ = xₙ² − 2 with x₀ = 0.5 and obtains the sequence 0.5, −1.75, 1.0625, −0.871, −1.241, ... Explain what is happening.

2 marksstandard

Quick recall flashcards

Iteration Process
Put xₙ into formula to get xₙ₊₁. Repeat until values converge (settle down).
Sum Formula
S_n = a(r^n - 1)/(r - 1) where r is common ratio

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