早教吧作业答案频道 -->数学-->
计算题14、(12分)计算:[x(x2y2-xy)-y(x2-x3y)]÷x2y15、(1814、(12分)计算:[x(x2y2-xy)-y(x2-x3y)]÷x2y15、(18分)已知m2=n+2,n2=m+2(m≠n),求m3-2mn+n3
题目详情
计算题 14、(12分) 计算:[x(x2y2-xy)-y(x2-x3y)]÷x2y 15、(18
14、(12分)
计算:[x(x2y2-xy)-y(x2-x3y)]÷x2y
15、(18分)已知m2=n+2,n2=m+2(m≠n),求m3-2mn+n3
14、(12分)
计算:[x(x2y2-xy)-y(x2-x3y)]÷x2y
15、(18分)已知m2=n+2,n2=m+2(m≠n),求m3-2mn+n3
▼优质解答
答案和解析
[x(x2y2-xy)-y(x2-x3y)]÷x2y
=[x2y(xy-1)+x2y(xy-1)]÷x2y
=2x2y(xy-1)/x2y
=2(xy-1)
=2xy-2
m2=n+2,n2=m+2
m2-n2=-(m-n)
(m-n)(m+n+1)=0
m≠n,m+n+1=0
,m+n= -1
m2+n2+2mn=1,m2+n2=m+2+n+2=3
mn= -1
m3-2mn+n3=(m+n)(m2-mn+n2)-2mn
=(m+n)(n+2-mn+m+2)-2mn
= -(3-mn)-2mn=-3-mn= -3+1= -2
=[x2y(xy-1)+x2y(xy-1)]÷x2y
=2x2y(xy-1)/x2y
=2(xy-1)
=2xy-2
m2=n+2,n2=m+2
m2-n2=-(m-n)
(m-n)(m+n+1)=0
m≠n,m+n+1=0
,m+n= -1
m2+n2+2mn=1,m2+n2=m+2+n+2=3
mn= -1
m3-2mn+n3=(m+n)(m2-mn+n2)-2mn
=(m+n)(n+2-mn+m+2)-2mn
= -(3-mn)-2mn=-3-mn= -3+1= -2
看了 计算题14、(12分)计算:...的网友还看了以下:
把下列格式分解因式(1)2a^4b62-463b^2+10ab^4;(2)10(x-y)^2-5(x 2020-03-31 …
关于一道数学题化简|2x+1|-|x-5|设2x+1=0,x-5=0x=-1/2,x=5当x<-1 2020-05-17 …
五道微积分题,第一题1/sqr(9x^2-6x+7)1/3ln|3x-1|+sqr(9x^2-6x 2020-06-10 …
lim(x→5)1-√(x-4)/(x-5)=lim-[√(1+(x-5))-1]/(x-5)如何 2020-07-09 …
4/1+x+4/(1+x)^2+4/(1+x)^3+4/(1+x)^4+104/(1+x)^5=9 2020-07-18 …
(30-x0.5)×(10+x)-(30-x0.5)×1-x0.5×0.5=275解方程(30-x 2020-07-19 …
解三元一次方程组x:y=5:3(1)x:z=7:3(2)2x-y-z=35(3)5x+6y+2z= 2020-08-03 …
1.解下列方程组:(1){2y-1/x+1=1/4(2){3/x-1/y=5{y+1/x-3=1/2 2020-10-31 …
有5道求积分题遇到困难第一题1/sqr(9x^2-6x+7)1/3ln|3x-1|+sqr(9x^2 2020-11-30 …
某校图书馆的藏书在两年内从5万册增加到7.2万册,若设平均每年增长的百分率为x,则根据题意所列方程正 2020-12-04 …