=x(x+y)〔(x-y)-(x+y)〕
=x(x+y)(-2y)
=-2xy(x+y)
把x+y=1,xy=-1/2代入-2xy(x+y)可得：
-2xy(x+y)
=-2*(-1/2)*1
=1
x(x+y)(x-y)-x(x+y)^2
= x(x+y)(x-y-x-y)
=-2xy(x+y)
=-2*(-1/2)*1
=1
已知:x+y=1,xy=-1\/2,则x(x+y)(x-y)-x(x+y)^2=
解：x(x+y)(x-y)-x(x+y)^2 =x(x+y)〔(x-y)-(x+y)〕=x(x+y)(-2y)=-2xy(x+y)把x+y=1,xy=-1\/2代入-2xy(x+y)可得：-2xy(x+y)=-2*(-1\/2)*1 =1
已知x+y=1,xy=-1\/2,利用因式分解求x(x+y)-x(x+y)的平方的值
=x*(1-x)=x*(x+y-x)=x*y =-1\/2
已知x+y=1,,xy=-二分之一,利用因式分解求 x(x+y)(x-y)-x(x+y)平方
解 x(x+y)(x-y)-x(x+y)平方 =x(x+y)[(x-y)-(x+y)]=x(x+y)(-2y)=-2xy(x+y)=-2×(-1\/2)×1 =1 记得采纳
x+y=1,xy=-1\/2,求x(x+y)(x-y)-x(x+y)2
解:原式=x(x+y)(x-y-x-y)=-2xy(x+y)=-1
已知x+y=1,xy=负二分之一,求x(x+y)(x-y)-x(x+y)的二次方的值
x(x+y)(x-y)-x(x+y)的二次方 =x(x+y)(x-y-x-y)=-2xy(x+y);=-2×(-1\/2)×1 =1;如果本题有什么不明白可以追问，如果满意记得采纳 如果有其他问题请采纳本题后另发点击向我求助，答题不易，请谅解，谢谢。祝学习进步
已知:x+y=1,xy=-2分之一,利用因式分解求x乘括号x加y乘括号x减y减x乘...
x(x+y)(x-y)-x(x+y)^2 =x(x+y)(x-y-x-y)=-2xy(x+y)=-2*(-1\/2)*1 =1
已知x+y=1,xy=-二分之一,求x(x+y)(x-y)-x(x+y)²
已知x+y=1，xy=-二分之一，求x（x+y)(x-y)-x(x+y)² x（x+y)(x-y)-x(x+y)² =x(x+y)[(x-y)-(x+y)] =x(x+y)(x-y-x-y) =-2xy(x+y) =-2×(-1\/2)×1 =1 已知集合A=｛（x,y)丨y=x2-1,x∈R｝，B=｛（x,y)丨y=-x2+7,x...
当x(x+y)(x-y)-x(x+y)²进行因式分解,并求当x+y=1,xy=-1\/2时此式...
因式分解结果 x（x+y）（x-y）-x（x+y）²=x（x+y）[（x-y）-（x+y）]=-2xy(x+y)当x+y=1,xy=-1\/2时此式 等于-2*（-1\/2）*1=1
谁能给我50道初二(上)的因式分解的题和20道化简求值的题啊?(带答案...
1. 已知：x+y=1,xy=-1\/2,利用因式分解求：x(x+y)(x-y)-(x+y)的平方的值。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\/2]*1 =1 2. 已知：a+b+c=11 求2a^2+2b^2+2c^2+4ab+4ac+4bc的值 2a^2+2b^2+2c^2+...
