第1个回答 2011-03-14
x^2-2根号2x+1=0
x^2-2根号2x=-1
x^2-2根号2x+2=-1 +2
(x-根号2)^2=1
x-根号2=±1
x1=根号2-1
x2=根号2+1
第2个回答 2011-03-14
x^2-2根号2x+1=0
x^2-2根号2x+2-1=0
x^2-2根号2x+2=1
(x-根号2)^2=1
x-根号2=±1
x1=根号2+1 x2=根号2-1
第3个回答 2011-03-14
x^2-2√2x+1=0
x^2-2√2x+2-1=0
x^2-2√2x+(√2)^2-1=0
(x-√2)^2-1=0
(x-√2-1)(x-√2+1)=0
x=√2+1或x=√2-1