请说明代数式X³-7X²y+2+ 6X³+2X²y-7X³+5X
试说明代数式-(3x²y+10x³)+3x³6x³y+3x的值与x,y都无关
约分下列分式(x-y)/(y-x)³(x²-9)/(6-2x)(x²-1)/(x-x
请说明代数式x的三立方-7x平方y+2+6x立方+2x平方y-7x三立方+5x平方y的值与字母x,y的取值无关
试说明:多项式(5x³-7x³y+3x²y)+2x³-(-7x³y+3
合并同类项:-6x²y-x+5x²y-2x+x³y+3x
若x、y满足2x+y=6,x-3y=1,求7y(x-3y)²-2(3y-x)³的值
已知x²+y²+5=2x+4y,求代数式(2x²-(x+y)(x-y))x((x+y-1)
试说明代数式:—(3x²y+10x³)+3x³+6x³y+3x²y—(
1/x²×x³+x的7次方÷x² 2/、【(x-y)²+(x+y)(x-y)]÷
(1)已知:x+y=5,x²+y²=13,求代数式x³y+2x²y²+
设x-2的绝对值+(y+1/4)平方=0,试求代数式x²(x²-xy+y)-x(x³-2x
求因式分解(x-y)²-2(x-y)³和(x+y)(x-y)-x(x-y)