1.2 Proof Methods

A Bogus Proof by Contradiction

Which step(s) contain the logical error?

Bogus Claim: \(\sqrt{4}\) is irrational.

Exercise 1



This proof makes the same logical error twice. It claims that since \(n^2\) is a multiple of 4, then 4 must also be a factor of \(n\). However, only 2 must be a factor of \(n\).