作业帮6x(x-y)二次 3(y-x)三次
来源：学生作业帮助网 编辑：作业帮 时间：2024/05/21 13:05:08
晕~~这时三次方程啊!高次方程~~!咋解?不会!可能大学会讲!听老师说须要试根!你试试看能不能解!
{2/3x-2/(x+y)[(x+y)/3x-x-y]}/【(x-y)/x】的负二次方={2/3x-[2/(x+y)]*[(x+y)-3x(x+y)]/(3x)}*[x/(x-y)]^2={2/3x-
解原式={2/3X-2/(X+Y)[(X+Y)/3X-(X+Y)]}/(X-Y)*X={2/3X-2/(X+Y)*(X+Y)/3X+2/(X+Y)*(X+Y)}*X/（X+Y）=[2/3X-2/3X+
解,由方程2可得：1/(x+y)=9/(x-y)-1---(1)所以4/(x+y)=36/(x-y)-4代入方程1,得42/(x-y)=7所以x-y=6代入(1)式得x+y=2联立可得x=4,y=-2
{①(x-y+6)(2x+y-1)=0②(2x+3y+2)(3x-2y+1)=0（1）(x-y+6)=0(2x+3y+2)=0解得x=-4y=2（2）(x-y+6)=0(3x-2y+1)=0解得x=1
原式=-3x²y-10x^3+3x^3+6x^3y+3x²y-6x^3y+7x^3=0很明显,代数式的值与x,y无关
(2x+4y)(x-2y)=2(x+2y)(x-2y）=2(x^2-4y^2)(2x+3y)(2x-3y)(4y^2+9y^2)=（4x^2-9y^2)(4y^2+9y^2)=16x^4-81y^4
3x^2(x-y)+6x(y-x)=3x^2(x-y)-6x(x-y)=(x-y)(3x^2-6x)=3x(x-y)(x-2)
4x四次y二次-5x二次y二次-9y二次=y^2(4x^4-5x^2-9)=y^2(x^2+1)(4x^2-9)=y^2(x^2+1)(2x+3)(2x-3)
x²-y²=(x+y)(x-y)=6因为x+y=3所以(x+y)(x-y)/(x+y)=6/3x-y=2
联立两方程,-3x^2-6x+5=x^2-x-k4x^2+5x-5-k=0因为只有一个公共点,所以△
x二次方+y二次方-4x+6y+13=0(x-2)²+(y+3)²=0则有：x-2=0y+3=0解得：x=2；y=-3(3x+y)²-3(3x-y)(x+y)-(x-3y
答：x=-1,y=2(3x²y-2xy²)-(xy²-2x²y)-(3x²y²+2x²y)-(-3x²y²-2
3x（x-y）三次方-6y（y-x）二次方=3x(x-y)³-6y(x-y)²=3(x-y)²(x²-xy-2y)
显然3x+y+6=0x+y+2=0两式相减得2x=-4x=-2y=0所以3x+2y=-6
原式=x²y(x-y)²-2xy(x-y)²=xy(x-y)²(x-2)再问：原式=x²y(x-y)²-2xy(y-x)²再答：对
第一题：(x-2y)*x^3-(y-2x)*y^3=x^4-2x^3y-y^4+2xy^3=(x^4-y^4)-2xy(x^2-y^2)=(x^2+y^2-2xy)(x^2-y^2)=(x-y)^2*
-x²+6x-8=-(x²-6x+8)=-(x²-6x+9-1)=-(x-3)²+1当x=3时,该二次函数取得最大值.最大值为1(2x+3y)²-(2x-3y)
3x+3y+2x-2y=364x+4y-5x+5y=2=>5x+y=36(1)-x+9y=2(2)(1)+(2)*5得46y=46y=1x=7
结果是3（x-y）的2次方与（2x-5y）的积3（x-y）的2次方乘以2（x-y）-3（x-y）乘以3y,提取3（x-y）的2次方得3（x-y）的2次方乘以（2x-2y-3y）,合并得：3（x-y）的