1/X的平方-4X+4-X/X的平方-4+1/2X+4=1/(x-2)² - x/(x+2)(x-2) + 1/2(x+2)=[2(x+2)-2x(x-2)+(x-2)²]/ [2(x+2)(x-2)²]=(2x+4-2x²+4x+x²-4x+4)/ [2(x+2)(x-2)²]=(-x²+2x+8)/ [2(x+2...&#？？？这是什么意思