已知x+y=5,xy=3 (1)x²+y²的值 (2)求x-y(x>y)的值
已知x-y=1,y≠0,求{(x+2y)²+(2x+y)(x+4y)-3(x+y)(x-y)}÷y的值.
已知x+y=5,xy=3 (1)x²+y²的值 (2)求x-y(x>y)的值
已知x-5y=0,求分式x²-2xy+y²/3x+y × (y-x)的值
已知,x-y=5,xy=6,求(x+y)²-2x-2y+1的值
已知1/x-1/y=4,求(2x+xy-2y)/(x-2xy-y)的值
1、已知实数x、x满足x²+y²-xy+2x-y+1=0,试求x、y的值.
已知x-3y=0,y≠0,求x²-2xy+y²分之2x+y×(x-y)的值
已知x²-x-2xy+y+y²,求代数式½(x²+y²)-xy的值
已知xy=2,x-y=3,求(x+y)(x-y)-y^2-(6x^2y-2xy^2)/2y的值.
已知xy=-2,x-y=3,求(x+y)(x-y)-y平方+(x-y)平方-(6x2y-2xy平方)/2y的值
X²+Y²=9.(X+Y)²=13 求XY和X+Y的值
初中数学分式已知x/y=2,求(x*x-xy+3y*y)/x*x+xy+6y*y的值