如果x/2-y/3,那么(7x²-y²)/(x-2xy+3y²)= .答案是不是等于1?

如果x/2-y/3,那么(7x²-y²)/(x-2xy+3y²)= .答案是不是等于1?
如果x/2-y/3,那么(7x²-y²)/(x-2xy+3y²)= .答案是不是等于1?

如果x/2-y/3,那么(7x²-y²)/(x-2xy+3y²)= .答案是不是等于1?
x/2-y/3=0
x/2=y/3
x=2y/3
(7x²-y²)/(x²-2xy+3y²)
= （7*4y²/9-y²)/(4y²/9-2*2y/3*y+3y²)
=（19y²/9）/（19y²/9）
=1
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题目有问题啊，应该是x/2-y/3=0，那么(7x²-y²)/(x²-2xy+3y²)=


x/2-y/3=0
设x=2k y=3k
则
(7x²-y²)/(x²-2xy+3y²)
=(28k²-9k²)/(4k²-12k²+27k²)
=(19k²)/(19k²)
=1

x/2-y/3=0
∴x/y=2/3
(7x²-y²)/(x ² -2xy+3y²)
=[7(x/y)²-1]/[(x/y)²-2(x/y)+3]
=(28/9-1)/(4/9-4/3+3)
=1