1/2x-(2x-2/3y²)+(-3/2x+1/3y²)
已知x-y=1,y≠0,求{(x+2y)²+(2x+y)(x+4y)-3(x+y)(x-y)}÷y的值.
先化简再求值:(x-2y)²-(x+2y)(x-2y)-(x-3y)(x-y).其中x²+9y
化简 (x+y)(x²-xy+y²) ; 3(2x-1)(x+6)-5(x-3)(x+6)
(1):(x+2y)²-(x+y)(3x-y) (2):(2x+3y)²-(2x-3y)²
已知x²+|y+x|=x-1/4,求(3x+y)²(2x-y)²-(4x²+y&
运用乘法公式(x+y+1)(x+y-1)(2x-y-3)²(2x-y-3)³【(x+2)(x-2)】
(1)已知x+y=6,x²-y²=5,求x-y的值(2)若x+y=3,x²+y²
计算3x[xy-2x(1/y-x/3]+3y(x²-y²)
(3x-y)²-2x(4x-5y)-(x+2y)²
先化简,在求值:(x-y)²+(3x-2y)(2x+y)-x(6x-y)
因式分解:(1)x²+x (2)4x²-9y (3)x²y-4y
已知:3x=8y.求(1)x+y/y (2)2x+3y/x-2y