x+y=5怎么解 将x(x+y)(x-y)-x(x+y)2进行因式分解,并求当x+y=1,xy=?12时此式的值
将x(x+y)(x-y)-x(x+y)2进行因式分解,并求当x+y=1,xy=?12时此式的值
将x(x+y)(x-y)-x(x+y)2进行因式分解,并求当x+y=1,xy=?12时此式的值
x(x+y)(x-y)-x(x+y)2=x(x+y)[(x-y)-(x+y)]=-2xy(x+y).
当x+y=1,xy=-
时,原式=-2×(-
1 2)×1=1.
将x(x+y)(x-y)-x(x+y)2进行因式分解,并求当x+y=1007,xy=-1时此式的值
解
x(x+y)(x-y)-x(x+y)²
=x(x+y)[(x-y)-(x+y)]
=x(x+y)(-2y)
=-2xy(x+y)
=-2×(-1)×1007
=2×1007
=2014
将x(x+y)(x-y)-x(x+y)²进行因式分解并求当x+y=1,xy=-2分之1时原式的值
你可以试着模仿这2题
将x(x+y)(x-y)-x(x+y)2进行因式分解,并求当x+y=1007,xy=-1时此式的值
解
x(x+y)(x-y)-x(x+y)²
=x(x+y)[(x-y)-(x+y)]
=x(x+y)(-2y)
=-2xy(x+y)
=-2×(-1)×1007
=2×1007
=2014
利用因式分解求x(x+y)(x-y)-x(x+y)^2的值,其中x+y=1,xy=1/2.
解∶x﹙x+y﹚﹙x-y﹚-x﹙x+y﹚²
=x﹙x+y﹚﹙x-y﹚-x﹙x+y﹚﹙x+y﹚
=x﹙x+y﹚[﹙x-y﹚-﹙x+y﹚]
=x﹙x+y﹚﹙x-y-x-y﹚
=x﹙x+y﹚﹙﹣2y﹚
=﹙﹣2xy﹚﹙x+y﹚
=﹙﹣2﹚× ½× 1
=﹣1
利用因式分解求x(x+y)(x-y)-x(x+y)的值,其中x+y=1,xy=1/2。
原式=(X2-XY)*(X+Y)-X2-XY
=X2-XY-X2-XY(因为X+Y=1)
=-2XY
=-1(因为XY=12)
X2就是X的平方,给点分谢谢
利用因式分解求x(x+y)(x-y)-x(x+y)^2的值,其中x+y=1,xy=2分之1
x(x+y)(x-y)-x(x+y)^2
=x(x+y)(x-y-x-y)
=-2xy(x+y)
=-2x(1/2)x1
=-1

已知:x+y=1,xy=2分之1,利用因式分解求x(x+y)(x-y)-x(x+y)^2的值
x(x+y)(x-y)-x(x+y)^2
=x(x+y)(x-y-x-y)
=-2xy(x+y)
=-2*(-1/2)*1
=1
因式分解 x^2(x+y)(y-x)-xy(x+y)(x-y)
x^2(x+y)(y-x)-xy(x+y)(x-y)
=x^2(x+y)(y-x)+xy(x+y)(y-x)
=x(x+y)(y-x)(x+y)
=x(x+y)^2(y-x)
因式分解 x^2(x+y)(x-y)-xy(x+y)(y-x)
x^2(x+y)(x-y)-xy(x+y)(y-x)
=x^2(x+y)(x-y)+xy(x+y)(x-y)
=(x+y)(x-y)(x^2+xy)
=x(x+y)(x-y)(x+y)
=x(x-y)(x+y)^2
实际上(x+y)(x-y)从上步到下步都没变的
就只有(x^2+xy)=(x*x+x*y)=x(x+y)
结果就变成了x(x+y)(x-y)(x+y
已知:x+y=1,xy=-1/4,利用因式分解求:x(x+y)(x-y)-x(x+y)^2的值
x(x+y)(x-y)-x(x+y)^2
=x(x+y)(x-y-x-y)
=-2xy(x+y)=1/2