2y²-4y+1=0
已知x-y=1,y≠0,求{(x+2y)²+(2x+y)(x+4y)-3(x+y)(x-y)}÷y的值.
y''+y'-2y=0的通解
x/x-1=y²+4y-2/y²+4y-1则y²+4y+x等于多少.求详细的解答过程,要快
用因式分解法解方程:(y-1)²+2y(1-y)=0
若|x+2y-1|+y²+4y+4=0,求(2x-y)²-2(2x-y)(x+2y)+(x+2y)&
计算:(1)2/(x+y)+4y/x²-y²(2)x²/x+y-x+y
已知x²+5y²-4xy+2y+1=0,求2x-y的值
【(X²+Y²)-(X-Y)²+2Y(X-Y)】/4Y=1,求4X/4X²-Y&
(3x-2)²+2x-y-3的绝对值=0,求5(2x-y)-2(6x-2y+2)+(4x-3y-2分之1)
已知实数x、y,满足方程x²+y²-4x+1=0,求:(1)y÷x的最大 值和最小值;(2)y-x
先化简,再求值:(y-2)(2y²-3y+9)-y(y²-2y+15),其中Y²-4Y-4
x²+y²-4x+6y+13=0,求(3x+y)²-3(3x+y)(x+y)-(x-3y)