化简求值x²-2x分之x²-1+2x-x²分之x-1,其中x=3

化简求值x²-2x分之x²-1+2x-x²分之x-1,其中x=3
化简求值x²-2x分之x²-1+2x-x²分之x-1,其中x=3

化简求值x²-2x分之x²-1+2x-x²分之x-1,其中x=3
=(x²-1)/(x²-2x)-(x-1)/(x²-2x)
=(x²-1-x+1)/(x²-2x)
=(x²-x)/(x²-2x)
=x(x-1)/x(x-2)
=(x-1)/(x-2)
当x=3时
原式=(3-1)/(3-2)=2

解
(x²-1)/(x²-2x)+(x-1)/(2x-x²)
=(x²-1)/(x²-2x)-(x-1)/(x²-2x)
=(x²-1-x+1)/(x²-2x)
=(x²-x)/(x²-2x)
=(x-1)/(x-2)
=(3-1)/(3-2)
=2

解:原式=(x^2-1)/(x^2-2x)-(x-1)/(x^2-2x)=(x^2-x)/(x^2-2x)=(x-1)/(x-2)=(3-1)/(3-2)=2。