已知X²-5X-2007=0则代数式(X-2)²-(X-1)²+1/X-2的值为
原式=(x-2)²-(x-1)²+1²/x-2
=(x-2)²-(x-1-1)(x-1+1)/x-2
=(x-2)²-(x-2)x/x-2
=x-2(x-2-x)/x-2
=-2