若3x^2+xy-2y^2=0,求(x+y/x-y+4xy/y^2-x^2)除以(x^2+2xy-3y^2/x^2-9y^2)的值
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![若3x^2+xy-2y^2=0,求(x+y/x-y+4xy/y^2-x^2)除以(x^2+2xy-3y^2/x^2-9y^2)的值](/uploads/image/z/318860-44-0.jpg?t=%E8%8B%A53x%5E2%2Bxy-2y%5E2%3D0%2C%E6%B1%82%EF%BC%88x%2By%2Fx-y%2B4xy%2Fy%5E2-x%5E2%29%E9%99%A4%E4%BB%A5%28x%5E2%2B2xy-3y%5E2%2Fx%5E2-9y%5E2%29%E7%9A%84%E5%80%BC)
若3x^2+xy-2y^2=0,求(x+y/x-y+4xy/y^2-x^2)除以(x^2+2xy-3y^2/x^2-9y^2)的值
若3x^2+xy-2y^2=0,求(x+y/x-y+4xy/y^2-x^2)除以(x^2+2xy-3y^2/x^2-9y^2)的值
若3x^2+xy-2y^2=0,求(x+y/x-y+4xy/y^2-x^2)除以(x^2+2xy-3y^2/x^2-9y^2)的值
3x^2+xy-2y^2=0
(3x-2y)(x+y)=0
因为4xy/(y^2-x^2)有意义,所以,x+y≠0
所以,3x-2y=0
y=3x/2
(x+y/x-y+4xy/y^2-x^2)除以(x^2+2xy-3y^2/x^2-9y^2)
=[(x+y)^2-4xy]/(x-y)(x+y)除以(x+3y)(x-y)/(x-3y)(x+3y)
=(x-y)^2/(x-y)(x+y)除以(x-y)/(x-3y)
=(x-y)/(x+y)除以(x-y)/(x-3y)
=(x-3y)/(x+y)
=(x-3*3x/2)/(x+3x/2)
=(-7x/2)/(5x/2)
=-7/5