计算:3y(y-4)(2y+1)-(2y-3)(4y²+6y-9)
1.((y+2x)(-2x+y)+4(x+2y)^2)/3y 2.(2(x-y)^3-8(x-y)^2(x+y)+6y(
计算:(3x-4y)-[-(2y+x)+(x-3y)]-6x
啊啊啊啊!做题代数式9-6y-4y*y=7,则2y*y+3y+7的值是( )
计算4xy+(x-2y)的平方+(x+3y)(3y-x)
计算:(x-4y)(2x+3y)-(x+2y)(x-y).
已知x-y=1,y≠0,求{(x+2y)²+(2x+y)(x+4y)-3(x+y)(x-y)}÷y的值.
若|x+2y-1|+y²+4y+4=0,求(2x-y)²-2(2x-y)(x+2y)+(x+2y)&
已知y²-3y+1=0,求下列分式的值 y²+(1/y²) y²/y的4次方+y
因式分解 (1).(x+y)(x+y-6)+9 (2).x²-16y²-x-4y
先化简再求值:(x-2y)²-(x+2y)(x-2y)-(x-3y)(x-y).其中x²+9y
(X-3Y)(X+3Y)-(X+2Y)(X-4Y)-(2X-Y)2的平方
已知7/3*根号(9y)-y-2y*1/y=-2,求y的值