(x+y)²=1(x-y)²=17,x²+y²=?xy=?
(x+y)²=1(x-y)²=17,x²+y²=?xy=?
已知x+y=1,xy=-二分之一,求x(x+y)(x-y)-x(x+y)²
已知x²+y²-8x+6y+25=0,求(x-y+4xy/x-y)(x+y-4xy/x+y)
x²+xy/(x-4y)(x+y),其中x=4,y=-1
已知x/y=2,求2x(x+y)-y(x+y)/4x²-4xy+y²
一.x-y=2,则x²-2xy+y²= 二.x-y=-1,xy=3,则x³y-2x
2x²-3xy=y²=0(x,y不得o)求x/y+y/x
已知实数x,y满足x²+y²-xy+2x-y+1=0 求x y
4/X+1/Y=2,XY=-1,求代数式4Y-X/X-2Y/(x+2y-12Y²/x-2y)的值
已知实数x,y满足5x²+2y²+1=6xy+4x-2y,则x²-xy+2000y
若x=1/2,y=1 求x(x²+xy+y²)-y(x²+xy+y²)+3xy(
若x+y=10 xy=-1 则x²+y²=(x+y)²-2xy=