若x/2=y/3,则分式7x^2-y^2/x^2-2xy+3y^2的值是 多少?已知2x-y,求分式(1+3y^3/x^3-y^3)/(1+2y/x-y)的值?
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![若x/2=y/3,则分式7x^2-y^2/x^2-2xy+3y^2的值是 多少?已知2x-y,求分式(1+3y^3/x^3-y^3)/(1+2y/x-y)的值?](/uploads/image/z/570870-54-0.jpg?t=%E8%8B%A5x%2F2%3Dy%2F3%2C%E5%88%99%E5%88%86%E5%BC%8F7x%5E2-y%5E2%2Fx%5E2-2xy%2B3y%5E2%E7%9A%84%E5%80%BC%E6%98%AF+%E5%A4%9A%E5%B0%91%3F%E5%B7%B2%E7%9F%A52x-y%2C%E6%B1%82%E5%88%86%E5%BC%8F%EF%BC%881%2B3y%5E3%2Fx%5E3-y%5E3%EF%BC%89%2F%EF%BC%881%2B2y%2Fx-y%EF%BC%89%E7%9A%84%E5%80%BC%EF%BC%9F)
若x/2=y/3,则分式7x^2-y^2/x^2-2xy+3y^2的值是 多少?已知2x-y,求分式(1+3y^3/x^3-y^3)/(1+2y/x-y)的值?
若x/2=y/3,则分式7x^2-y^2/x^2-2xy+3y^2的值是 多少?
已知2x-y,求分式(1+3y^3/x^3-y^3)/(1+2y/x-y)的值?
若x/2=y/3,则分式7x^2-y^2/x^2-2xy+3y^2的值是 多少?已知2x-y,求分式(1+3y^3/x^3-y^3)/(1+2y/x-y)的值?
由已知得:x=2y/3,代入欲求式子,得
(7x^2-y^2)/(x^2-2xy+3y^2)
=[7*(2y/3)^2-y^2]/[(2y/3)^2-2*2y/3*y+3y^2]
=(28y^2/9-y^2)/(4y^2/9-4y^2/3+3y^2)
=(19y^2/9)/(19y^2/9)
=1
1