Problem
NT-B1-M11-P001 Two Consecutive Numbers
#1
★☆☆☆☆ Level 1 of 5
Prove that \(n(n+1)\) is divisible by \(2\) for every integer \(n\).
Of two consecutive integers, one is even.
The numbers \(n\) and \(n+1\) have opposite parity, so one is divisible by \(2\). Hence their product is divisible by \(2\).
Warm-up on basic divisibility.