证明x³/y+y³/x≥1/2(x+y)²,x>0,y>0
求因式分解(x-y)²-2(x-y)³和(x+y)(x-y)-x(x-y)
2x+y=0,求4x²+2xy(x+y)+y³
1、x(x-y)(x+y)-x(x+y)^2
若|x+2y-1|+y²+4y+4=0,求(2x-y)²-2(2x-y)(x+2y)+(x+2y)&
(x-y)的四次方(x-y)-2(x-y)²(y-x)³等于?
(x-y)³+9(x-y)-6(x-y)²
(x-y)³(x-y)²(y-x)等于多少
若|x+y-1|+(x-y-2)²=0,求代数式(x+2y)(x-2y)-(2x-y)(-y-2x)的值.
2x²+1/2y²-2x-3y+5=0,求(2x√9x-y²√x/y³)-(√1
已知|x+y+2|+(2x-3y-1)²=0 求 ⑴x、y的值 ⑵2x³-x²-3y
证明不等式:(根号x-根号y)(x-y)≥0(其中x,y皆为正数)
证明x,y趋于0时,x^2y/(x^4+y^3)的极限不存在