作业帮xy²-2xy 2y-4
来源：学生作业帮助网 编辑：作业帮 时间：2024/05/12 10:09:00
xy²-2xy+2y-4=xy(y-2)+2(y-2)=(y-2)(xy+2)
1.2(Xy+Xy)-3(Xy-xy)-4Xy=2*2xy-0-4xy=4xy-4xy=02.1/2ab-5aC-(3acb)+(3aC-4aC)=1/2ab-5ac-3acb-ac=1/2ab-6a
[（xy+2）（xy-2）-2x2y2+4]÷（xy）=（x2y2-4-2x2y2+4）÷xy=-x2y2÷xy=-xy,当x=10,y=1/25时,原式=-2/5．
[(xy+2)(xy-2)-2x^2y^2+4]/(xy)=[(x^2y^2-4)-2x^2y^2+4]/(xy)=-x^2y^2/xy=-xy=-10*(-1/25)=2/5
xy^2-4x=x(y+2)(y-2)-2a^2+4ab-2b^2=-(a-b)^2a^2(x-y)+b^2(y-x)=(x-y)(a+b)(a-b)(a^2+b^2)^2-4a^2b^2=(a+b)
(-3x^y+2xy)-(4x^+xy)=-3x^y+2xy-4x^-xy=-3x^y+xy-4x^所以填上-3x^y+xy-4x^
[（xy-2）（xy+2）-2x2y2+4]÷（xy），=（x2y2-4-2x2y2+4）÷（xy），=（-x2y2）÷（xy），=-xy
x^3y(-4y)^2+(-7xy)^2*(-xy)-5xy^3*(-3x)^2=16x^3y^3-49x^3y^3-45^3y^3=-78x^3y^3如果本题有什么不明白可以追问,
-3(2x²-xy)+4(x²+xy-6)=6x²+3xy+4x²+4xy-24=-2x²+7xy-24
xy(y-2)+2(y-2)下步不写了能看懂吧?
原式=xy(y-2)+2(y-2)=(y-2)(xy+2)
xx+2xy-yy=-3两式相加即可
xy^-2xy+2y-4=xy（y-2）+2（y-2）=（xy+2）（y-2）
-3(2x^2-xy)+4(x^2+xy-6)=-6x^2+3xy+4x^2+4xy-24=-2x^2+7xy-24再问：thankyou~
∵x-y=4xy，∴2x+3xy-2yx-2xy-y=2(x-y)+3xyx-y-2xy=8xy+3xy4xy-2xy=112．故答案为：112．
3xy-3xy-xy+2yx=-xy+2xy=xy
=(x²y²-4-x²y²-xy+4)/(-2xy)=-xy/(-2xy)=1/2
5xy^2-[3xy^2-(4xy^2-2x^y)]+x^2y-xy^2=5xy^2-3xy^2+(4xy^2-2x^y)+x^2y-xy^2=5xy^2-3xy^2+4xy^2-2x^y+x^2y-
[(xy-2)(-xy-2)-4(xy-1)^2]除以(-xy)=[-x²y²+4-4(x²y²-2xy+1)]÷(-xy)=(-x²y²+