若(X-2)²+[2y+1]=0 则x³+y²=?
若|x+2y-1|+y²+4y+4=0,求(2x-y)²-2(2x-y)(x+2y)+(x+2y)&
若|x+y-1|+(x-y-2)²=0,求代数式(x+2y)(x-2y)-(2x-y)(-y-2x)的值.
若实数X,Y满足X²+Y²+4X-2Y +1=0,则X²-6X+Y²-2Y的最大
设x>1,y>0,若x^y+x^-y=2根号2,则x^y-x^-y等于
若x、y满足2x+y=6,x-3y=1,求7y(x-3y)²-2(3y-x)³的值
1/2 x²y·( )=2x³y-x²y²
已知|x+y+2|+(2x-3y-1)²=0 求 ⑴x、y的值 ⑵2x³-x²-3y
若3x-5y=0,则x+y/x=(),x-y/y=(),2x-3y/2x+3y=( )
(1)已知x+y=6,x²-y²=5,求x-y的值(2)若x+y=3,x²+y²
已知x=1/y,则(x-1/x)(y-1/y)等于 A、2x² B、2y² C、x²+y&
若|2x+y-1|+(x-2y)²=0,则x²+xy+y²的值为?
若|x+y+4|+(x-y+2)²=0,则3x+2y=( )