関連ワード:  square root 2 is a rational number    square root 2 is a rational number or not    under root 2 is a rational number    under root 2 is a rational number true or false    under root 2 is a rational number true or false with reason    under root 2 is a rational number or irrational    square root 2 is an irrational number    1 under root 2 is a rational number    under root 2 3 is a rational number    prove under root 2 is a rational number