已知:3X^2+XY-2Y^2=0,求(X+Y)/(X-Y)+4XY/(Y^2-X^2)÷(X^2+2XY-3Y^2)/(X^2-8Y^2)的值...

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已知:3X^2+XY-2Y^2=0,求(X+Y)/(X-Y)+4XY/(Y^2-X^2)÷(X^2+2XY-3Y^2)/(X^2-8Y^2)的值...
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已知:3X^2+XY-2Y^2=0,求(X+Y)/(X-Y)+4XY/(Y^2-X^2)÷(X^2+2XY-3Y^2)/(X^2-8Y^2)的值...
已知:3X^2+XY-2Y^2=0,求(X+Y)/(X-Y)+4XY/(Y^2-X^2)÷(X^2+2XY-3Y^2)/(X^2-8Y^2)的值.
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已知:3X^2+XY-2Y^2=0,求(X+Y)/(X-Y)+4XY/(Y^2-X^2)÷(X^2+2XY-3Y^2)/(X^2-8Y^2)的值...
3X^2+XY-2Y^2=0
分解因式得:(X+Y)(3X-2Y)=0
注意到所求分式里有Y^2-X^2作为分母,所以X+Y≠0,只能取3X-2Y=0
代入X=2Y/3即可