已知y=x³-x计算在x=2-搜答案-智慧作业帮

已知｜x—2｜+(y+3)2=0,计算(x+y)的2009次方x=2,y=-3(x+y)的2009次方=(2-3)的2009次方=-1

P=x²/x-y-y²/x-y=(x²-y²)/(x-y)=(x+y)(x-y)/(x-y)=x+y当x=2,y=1时p=3Q=(x+y)²-2y(x

1.(5x+y)(3x-5y)-(4x-y)(4y+x)=15x²-25xy+3xy-5y²-(16xy+4x²-4y²-xy)=15x²-22xy-

因为/x-2/是非负数,/y+1/是非负数非负数加非负数要等于零那么这两个非负数就是零所以x-2=0y+1=0则x=2y=-1楼主求你采纳我的我可是打了好久的字啊!

X+Y分之X-Y等于3x=-2yX+Y分之2(x-y)减X+Y分之3X+Y=(-x-3y)/(x+y)=1

因为(x-y)/(x+y)=3,则(x＋y)/(x－y)＝1/3则5(x-y)(x+y)-(x+y)/2(x-y)＝5*3-1/(3*2)=15-1/6=89/6

∵P=x2x-y-y2x-y=(x-y)(x+y)x-y=x+y,∴当x=2,y=-1时,P=2-1=1；又∵Q=（x+y）2-2y（x+y）=x2-y2,∴当x=2,y=-1时,Q=22-（-1）2

已知A=2x+y,B=2x-y,计算AB-B的平方=(2x+y)²-(2x-y)²=(2x+y+2x-y)(2x+y-2x+y)=4x2y=8xy看完了采纳哦~~祝学习进步!

A²﹣B²＝﹙2x+y﹚²﹣﹙2x-y﹚²＝﹙4x²﹢4xy﹢y²﹚﹣﹙4x²﹣4xy﹢y²﹚＝4x²﹢4xy

AxA-BxB=（2x+y）∧2-（2x-y）∧2=［（2x+y）+（2x-y）］［（2x+y）-（2x-y）］=4x﹒2y=8xy

A²-B²=(A+B)(A-B)=4X*2Y=8XY

已知2x+3y=3,计算4^x乘8^y=8再问：过程？再答：4^x乘8^y=2^(2x)*2^(3y)=2^(2x+3y)=2^3=8（2x+m）（2x-2013)=2x^2+(2m-2*2013)x

A^2-2AB=A（A-2B）=(2x-y)(2x-y-2(x+y))=(2x-y)(-3y)=3y^2-6xy

【】这个符号应该是绝对值的符号吧如果是这样的话也就是说【x+2】和【2y-3】都只能为0否则等式不成立得到x=-2y=-3/2那么3x-2y=-3-3的绝对值为3

即xy=2²-(√3)=4-3=1原式=[(x+y)²-(x-y)²]/(x+y)(x-y)*[-(x²-y²)/x²y²]=(x

A2-B2=（2x+y）2-（2x-y）2=（4x2+4xy+y2）-（4x2-4xy+y2）=4x2+4xy+y2-4x2+4xy-y2=8xy．

P=(x²-y²)/(x-y)=(x+y)(x-y)/(x-y)=x+yQ=x²+2xy+y²-2xy-2y²=x²-y²所以x=

解方程X=（6+M）/3Y=2M/3-2因为x>0y-6m

(x+2y)(x-2y)-(x+2y)-(x-2y)(2y-x)=x^2-4y^2-x-2y+(x^2-4xy+4y^2)=x^2-4y^2-x-2y+x^2-4xy+4y^2=2x^2-x-2y-4

x²+4y²=x²-4xy+4y²+4xy=(x-2y)²+4xy=12²+8=152再问：确定你对吗再答：对