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1.当x时,分式x+3/x-2有意义计算:1.y/x+y-x/x-y2.x-2/x-5-2x-1/(x-2)+1

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1.当x_≠2___时,分式x+3/x-2有意义

计算:1.y/x+y-x/x-y
=y(x-y)/(x+y)(x-y)-x(x+y)/(x+y)(x-y)
=(xy-y²-x²-xy)/(x²-y²)
=(x²+y²)/(y²-x²)

2.x-2/x-5-2x-1/(x-2)+1
=[(x-2)²-(2x-1)(x-5)+(x-2)(x-5)]/(x-2)(x-5)
=(x²-4x+4-2x²+11x-5+x²-7x+10)/(x-2)(x-5)
=14/(x-2)(x-5)
=14/(x²-7x+10)