若3x-2y=0,则4x/x²-xy+y²=?

若3x-2y=0,则4x/x²-xy+y²=?
若3x-2y=0,则4x/x²-xy+y²=?

若3x-2y=0,则4x/x²-xy+y²=?
x=2/3y
4x/(x^2-xy+y^2)=8/3y/(4/9y^2-2/3y^2+y^2)=8/3y/(7/9y^2)=24/(7y)

3x-2y=0
则3x=2y
y=3x/2
带入到
4x/x²-xy+y²=
=4x/（x^2-3x^2/2+9x^2/4)
=4x/(7x^2/4)
=4x*4/(7x^2)
=16/7x^2