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Specialist Mathematics · Unit 1 · Introduction to proof · Rational and irrational numbers

Prove irrationality by contradiction.

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Question 1

Prove that √3 is irrational.

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Question 2

When using proof by contradiction to show that $\sqrt{7}$ is irrational, after assuming $\sqrt{7} = \frac{p}{q}$ where $p$ and $q$ are integers with no common factors and $q \neq 0$, the next step in the proof requires showing that

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Question 3

Use proof by contradiction to prove that \(\sqrt{6}\) is irrational.

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More in Rational and irrational numbers

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Express rational numbers as terminating or eventually recurring decimals and vice versa.
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Prove results involving integers, e.g. proving that the product of two consecutive odd numbers is an odd number and 5𝑛2 + 3𝑛 + 6 ∀𝑛 ∈ ℤ is an even number.
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