Teaching Kids Programming – Two Ways to Prove Square Root of Two is Irrational (proof by contradiction and geometric infinite descent)

How to Prove √2 Is Irrational — Two Methods (Proof by Contradiction & Geometric Infinite Descent) Introduction The statement "√2 is irrational " means there are no integers [math]a[/math] and [math]b\neq 0[/math] with [math]\gcd(a,b)=1[/math] such that [math]\sqrt{2}=\dfrac{a}{b}[/math]. Method 1 — Proof by Contradiction Assume, for contradiction, that [math]\sqrt{2}[/math] is rational. Then there…