已知x²-y²=10,求[(x+y)的三次方-2y(x+y)²-4(x+y)]÷(x+y)
已知2x-y=10,求代数式[(x²+y²)-(x-y)²+2y(x-y)]÷4y的值?
已知2x-y=10,求代数式[x²+y²-(x-y)²+2y(x-y)]÷4y的值
已知x/y=2,求2x(x+y)-y(x+y)/4x²-4xy+y²
已知x+y=10,x的三次方+y的三次方=280,求x²+y²的值.
已知x-y= -2,xy=负四分之一,求-2x²y²+xy的三次方+x的三次方Y的值
已知xy=1,x+y=3,求代数式x三次方y+2x²y²+xy三次方的值
已知x+y=a,求(x+y)三次方×(2x+2y)三次方×(3x+3y)三次方的值
xy的三次方-2x²y²+x的三次方y=?
已知2x-y=10,求[(x²+y²)-(x-y)²+2y(x-y)]/4y的值
已知2x-y=10,求式子[(x^2+y^2)-(x-y)^2+2y(x-y)]/4y (4xy-2y²)/4
已知x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y
已知x+y=1,x²+y²=3,x三次方+y三次方等于多少