一.x-y=2,则x²-2xy+y²= 二.x-y=-1,xy=3,则x³y-2x
一.x-y=2,则x²-2xy+y²= 二.x-y=-1,xy=3,则x³y-2x
已知xy/x+y=1/2,则代数式3x-5xy+3y/-x+3xy-y=
已知X/Y=2,则X²+2XY-3Y²/X²-XY+Y²=?
若x+y=10 xy=-1 则x²+y²=(x+y)²-2xy=
已知实数x,y满足5x²+2y²+1=6xy+4x-2y,则x²-xy+2000y
若x+y=-1,则x^4+5x^3y+x^2y+8x^2y^2+xy^2+5xy^3+y^4=( )
已知x-y=4xy,则2x+3xy-2yx-2xy-y
若x+y分之xy=2,则-x+3xy-y分之3x-xy+3y=多少?
已知x/y=2,求2x(x+y)-y(x+y)/4x²-4xy+y²
若x=1/2,y=1 求x(x²+xy+y²)-y(x²+xy+y²)+3xy(
已知xy/x+y=2,则代数式3x-5y+8y/-x+3xy-y的值
x²+3y-xy-3x= x³-x²-x+= x²-1-2xy+y= a