(X+根号2)(X-根号2)=根号2-X
(X+根号2)(X-根号2)=﹣(x-√2)
(x+√2)(x-√2)+(x-√2)=0
(x-√2)(x+√2+1)=0
所以x-√2=0 x=√2
或者x+√2+1=0 x=﹣1-√2