已知:x = 1/2+√3 ,xy=1,则 x²y-xy²/x²-y².
已知2X-3√xy-2y=0(x>0)求2x²+xy-9y²分之x²+4xy-16y
已知x²-3xy+4x=3,y²+xy-4y+7=0,则xy-1/2(x²+y²
已知x=3 y=1\3,求3x²y-[2xy²-2﹙xy-3\2x²y﹚+xy]+3xy&
已知x+y=3 xy=-5 求x设abc=1 求x²+3xy+2y²/x²y+2xy
已知x²-xy=4,y²-xy=9求下面代数式的值(1)x²-2xy+y²;(2
已知(x+1)²+|y-1|=0,求2(xy-5xy²)-(3xy²-xy)得值
已知x²+y²=7,xy=-2.那么5x²-3xy-4y²-11xy-7x
已知x+y=5,xy=3,x³+y³=(x+y)(x²-xy+y²),则1/x&
已知x:y=3:2,求(x²+3xy)/(xy+2xy)
已知X/Y=2,则X²+2XY-3Y²/X²-XY+Y²=?
已知X²+Y²+X²Y²-4XY+1=0 求:(X-Y)^2008-(XY)^2
已知x+y=2,xy=1/2,求x³y+2x²y²+xy³