(x²-4x+4/x²-4)÷(x²-2x/x+2)-(1/x)+1
=(x-2)²/[(x-2)(x+2)]×(x+2)[x(x-2)]-(1/x)+1
=(x-2)/(x+2)×(x+2)/[x(x-2)]-1/x+1
=1/x-1/x+1
=1
∴ 聪聪说的有理.
∴只要原式有意义,无论x取何值,原式的值都为1.
聪聪说的有理.
∵ x2-4x+4 x2-4 ÷ x2-2x x+2 - 1 x +1= (x-2)2 (x+2)(x-2) × x+2 x ( x-2) - 1 x +1
= 1/ x - 1/ x +1
=1;
∴只要使原式有意义,无论x取何值,原式的值都相同,为常数1.