已知x÷y=3,则x²+2xy-3y²÷(x²-xy+y²)=?
2个回答
x÷y=3
∴x=3y
∴x²+2xy-3y²=9y²-3y²+2y·3y=12y²
∴x²-xy+y²=9y²-3y·y+y²=7y²
∴x²+2xy-3y²÷(x²-xy+y²)=12/7
相关问题
已知Y-x=3xy,求(5x+3xy-5y)÷(x-2xy-y)
已知1÷x-1÷y=-3,则(5x+xy-5y)÷(x-xy-y)的值为( )
已知1÷y-1÷x=5,求(2x+4xy-2y)÷(x-3xy-y)的值
已知x²+2xy+y²\xy-y²÷A=xy+y²\x²-2xy+y&
x*(9x^3y-3xy^2)÷(-3x^2y)= 【(x+y)^2-(x-y)^2】÷(-4xy)=
(xy-x²)÷[(x²-2xy+y²)÷xy]*[(x-y)÷x²]
已知x:y=2:3,求(x^2-y^2/xy)÷[(x+y)×(x-y/x)^3]÷(x/y^2)
(x√x+x√y)÷(xy-y^2)--(x+√xy+y)÷(x√x-y√y)
(x²y³+xy)(x²y³-xy)÷x²y³,其中x=3,
已知xy=-2,x-y=3,求(x+y)(x-y)-y^2+(x-y)^2-(6x^2y-2xy^2)÷2y