関連ワード:  under root 2 is an irrational number    under root 2 is an irrational number true or false    under root 2 is an irrational number prove that    square root 2 is an irrational number    5 under root 2 is an irrational number    3 under root 2 is an irrational number    under root 2 is irrational number proof    under root 2 is irrational number or not    under root 2 is a rational number    under root 2 is a rational number true or false