Question

se x=1+raiz de 2,entao x ao quadrado -2x+1 é igual a 

Answer 1

$x=1+\sqrt{2}\\\\\\ x^2-2x+1=(1+\sqrt{2})^2-2(1+\sqrt{2})+1=1+2\sqrt{2}+2-2-2\sqrt{2}=1$