(-x y)²*(-y² x)³÷(-xy^4)-搜答案-智慧作业帮

等于1/X*（X-Y）

解题思路：提取公因式进行分解解题过程：附件最终答案：略

[(x+y)²-(x-y)二次方]÷2xy=(x²+2xy+y²-x²+2xy-y²)÷2xy=4xy÷2xy=2

解题思路：本题主要利用完全平方公式进行因式分解即可求出结果解题过程：解:x²－6xy＋9y²=(x-3y)2

对.前提是x不等于y

xy-1+x-y

xy-1+x-y=XY+X-Y-1(加法交换律）=（XY+X）－（Y＋1）＝X（Y＋1）－(Y+1)（提取公因式X）=(Y+1)(X-1)（提取公因式Y+1）这样可以么?

4xy-(x+y)^2/xy(x+y)(x-y)÷x^2+xy-2y^2/x^2y+2xy^2=(4xy-x²-2xy-y²)/[xy(x+y)(x-y)]÷[(x-y)(x+2y

=xy(x-y)×[-xy/(x-y)]=-(xy)²=-x²y²

这题少括号了吧.

（xy-y^2)÷x-y/xy=y(x-y)×[xy/(x-y)]=xy²

(xy-x²）²÷（x-y)²/xy·x-y/x²=x²(y-x)²÷（x-y)²/xy·x-y/x²=x³y

[2x(x²y-xy²)+xy(xy-x²)]÷x²y=[2x²y(x-y)+x²y(y-x)]÷x²y=2(x-y)+(y-x)

这个,最后面那个减号前面是怎么回事?打括号没有?这个很重要!再问：x-y/x²是一个整体分数，3个分数，啊！！！再答：把前面分子分母同城xy然后两个合并就可以了啊！

解题思路：：∵x+y=0,x+13y=1，解得x=1/12,y=-1/12∴x²+12xy+13y²=1/144-1/12+13/144=14/144-1/12=2/144=1/72解题过程：已知x+

此题用的是完全平方公式（x+y)^2=x^2+2xy+y^2(x-y)^2=x^2-2xy+y^2所以（x+y)^2-(x-y)^2=4xy所以原式等于4xy/2xy=2

[(x-y)/(x+3y)]/[(x^2-y^2)/(x^2+6xy+9y^2)]-xy/(x+y)=(x-y)/(x+3y)*(x+3y)^2/(x-y)(x+y)-xy/(x+y)=(x+3y)/

原式=(x^2-y^2-x^2-2xy-y^2-2xy+2y^2-2xy)/xy=(-6xy)/xy=-6

(x-y)/x²÷(x²-2xy+y²)/xy×(xy-x²)=(x-y)/x²÷(x+y)²/xy×x(y-x)=(x-y)²/

[-(x-y)^2/xy]^-4*(y^2-xy/x)^3*(x^4/y^10)÷(xy-y^2/x)^-5=-y(y-x)^29^-x*27^y=3^-2x*3^3y=3^(-2x+3y)=3^(-