计算:[(x y)乘(x-y)]乘3x
来源:学生作业帮助网 编辑:作业帮 时间:2024/09/24 14:37:09
等于1/X*(X-Y)
原式=[(x+2y)(x-2y)/(x+y)²]÷[(x+2y)/x(x+y)]=(x+2y)(x-2y)x(x+y)/[(x+y)²(x+2y)]=(x-2y)x/(x+y)=(
这是一个初中竞赛题目与高中的主要运用公式x^3-y^3=(x-y)(x^2+xy+y^2)x^3+y^3=(x+y)(x^2-xy+y^2)其中(x-y)(x^2+xy+y^2)=x(x^2+xy+y
(-2x^2y^3)^2(xy)^3=4x^4y^3*x^3y^3=4x^(4+3)*y^(3+3)=4x^7y^6
3xy[2xy-x(y-2)+x-1]=3xy(2xy-xy+2x+x-1)=3xy(xy+3x-1)=3x^2y^2+9x^2y-3xy
3xy[2xy-x(y-2)+x]=3xy[2xy-xy+2x+x]=3xy(xy+3x)=3x²y²+9x²y
(X+Y)(X^2-XY+Y^2)=(x*x^2-x*xy+x*y^2)+(x^2y-xy^2+y^3)=x^3+y^3这个是立方和的公式,再给你一个x^3-y^3=(X-Y)(X^2+XY+Y^2)
这题少括号了吧.
【x²+xy/(x-y)】/【xy/(x-y)】=【x²(x-y)/(x-y)+xy/(x-y)】/【xy/(x-y)】={【x²(x-y)+xy】/(x-y)}/【xy
(xy-y^2)÷x-y/xy=y(x-y)×[xy/(x-y)]=xy²
[(x²+2xy+y²)/(xy-y²)][(x²-2xy+y²)/(xy+y²)]={(x+y)²/[y(x-y)]}{(x-y
=x^3-y^3-(x^3+y^3)=-2y^3^3表示三次方
直接分开相乘结果为xy(x^-1)+xy(y^-1)]=x+y
(xy-x²)乘(x-y)分之xy=-x(x-y)乘[(x-y)分之xy]=-x²y
X²+2xy+y²/xy乘x²-2xy+y²/xy+y²=(x+y)²/xy×(x-y)²/y(x+y)=(x+y)(x-y)
(-4xy)乘(xy+3x²y)=-4x²y²-12x³y²
3x平方乘(-2xy立方)=-6x立方y立方
解(x-y)/(xy-y²)=(x-y)/y(x-y)=1/y