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1.1 Proof by Contradiction

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Question 89

A structural engineer calculates that the side length, sss decimetres, of a square support column must satisfy the equation s2=13s^2 = 13s2=13 to meet safety specifications.

Use proof by contradiction to prove that sss is an irrational number.

(You may assume that for any integer nnn, if n2n^2n2 is a multiple of 13, then nnn is a multiple of 13).

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1.1 Proof by Contradiction Questions

  1. A Level
  2. /Maths
  3. /1.1 Proof by Contradiction

Practise Edexcel A Level Maths 1.1 Proof by Contradiction with exam-style questions for A Level Maths. 107 questions, matched to the Edexcel A Level Maths (9MA0) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.

Question bank