化简求值[1-(2x/x+y)]÷ (x²-2xy+y²/3x+3y)+(x²+xy/x²-y²)其中x=-7,y=6

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化简求值[1-(2x/x+y)]÷ (x²-2xy+y²/3x+3y)+(x²+xy/x²-y²)其中x=-7,y=6

化简求值[1-(2x/x+y)]÷ (x²-2xy+y²/3x+3y)+(x²+xy/x²-y²)其中x=-7,y=6
化简求值[1-(2x/x+y)]÷ (x²-2xy+y²/3x+3y)+(x²+xy/x²-y²)其中x=-7,y=6

化简求值[1-(2x/x+y)]÷ (x²-2xy+y²/3x+3y)+(x²+xy/x²-y²)其中x=-7,y=6
原式=[(y-x)/(x+y)]×[3(x+y)/(x-y)²]+x/(x-y)
=-1/(x-y) +x/(x-y)
=(x-1)/(x-y)
把x=-7,y=6代入上式,
原式=(-7-1)/(-7-6)=8/13