1/2x1/n+1x1/n+2怎么等于1/2(1/n+1-1/n+2)
来源:学生作业帮助网 编辑:六六作业网 时间:2024/12/25 01:19:19
1/2x1/n+1x1/n+2怎么等于1/2(1/n+1-1/n+2)1/2x1/n+1x1/n+2怎么等于1/2(1/n+1-1/n+2)1/2x1/n+1x1/n+2怎么等于1/2(1/n+1-1
1/2x1/n+1x1/n+2怎么等于1/2(1/n+1-1/n+2)
1/2x1/n+1x1/n+2怎么等于1/2(1/n+1-1/n+2)
1/2x1/n+1x1/n+2怎么等于1/2(1/n+1-1/n+2)
1/2x1/(n+1)x1/(n+2)
=1/2x1/((n+1)(n+2))
[由1=(n+2)-(n+1)]
=1/2x((n+2)-(n+1))/((n+1)(n+2))
乘法分配
=1/2x[(n+2)/((n+1)(n+2))-(n+1)/((n+1)(n+2))]
分子分母约去
=1/2x[1/(n+1)-1/(n+2)]
还有,梓萌是什么情况
1/2x1/n+1x1/n+2怎么等于1/2(1/n+1-1/n+2)
1x1+2.+nxn为什么等于1/6n(n+1)(2n+1)
x1+1 x1+2 x1+3 .x1+n x2+1 x2+2 x2+3 .x2+n .xn+1 xn+2 xn+3 .xn+n行列式求解
1x1/2 2x1/3.2007x1/2008怎么做
如何解柯西不等式已知X1,X2,...Xn是正数求证:(X1+X2+..=Xn)(1/X1+1/X2+...+Xn)小于等于N^2
数列xn满足x1/x1+1=x2/x3+3=x3/x3=5=.=xn/xn+2n-1,且x1+x2+x3+.+xn=8,则首项x1为?X1/(X1+1)=(X1+X2+...+Xn)/(X1+1+X2+3+X3+5+...+Xn+2n-1)是怎么来的?
设0Xn=(Xn-1)*[1-(Xn-1)]*[1-(Xn-1)-(Xn-1)^2]=-----=X1*[1-X1]*[1-X1-X1^2]*[1-X1-X1^2-X1^3]……[1-X1-X1^2-X1^3-X1^4-……X1^n];此式为(1)式。因为0
::::::如题已知X1到Xn的求和为1.求证(x1x2+x2x3+…+xnx1)*{[(x1/(x2^2+x2)]+…+[x...::::::如题已知X1到Xn的求和为1.求证(x1x2+x2x3+…+xnx1)*{[(x1/(x2^2+x2)]+…+[xn/(x1^2+x1)]}大于等于n/(1+n)
疑难数学问题火急求助x1^3-3x1^2+2x1+x2→x1(x1^2-2x1+2-x1)+x2→x1(3-x1)+x2 (怎么算出3-X1的)→3x1-x1^2+x2=2x1-x^2+x1+x2=-(x^2-2x1)+x1+x2=-1+2=1
已知X1~N(2,3),X2~N(4,1),且X1与X2相互独立,求2 X1+3,2 X1+3 X2,X1- 1/2 X2的分布.
1分钟做好X1 X2 随机变量.X1~N(0,1)X2~N(0,2)则A.X1=X2B.P{x1=x2}=1C.D(X1+x2)=3D.以上都不对
Xn+1-Xn=(-1/2)^n n∈N+ 且X1=1 求Xn
设随机变量X1,X2,…Xn(n>1)独立同分布,方差λ^2>0,令Y=(1/n)∑(i=1~n)Xi,则( )A.cov(X1,Y)=(λ^2)/n B.cov(X1,Y)=λ^2C.D(X1,Y)=[(n+2)/n]*(λ^2) D.D(X1,Y)=[(n+1)/n]*(λ^2)
若正数x1,x2,…,xn满足x1+x2+…+xn=1(n≥2)求证:x1÷(1- x1)+ x2÷(1- x2)+…+xn÷(1-xn)≥n÷(n-1)
已知数列{xn}满足x1=3,x2=x1/2,...,xn=1/2(xn-1+xn-2),n=3,4,...,则xn等于
数列xn满足x1/x1+1=x2/x3+3=x3/x3=5=.=xn/xn+2n-1,且x1+x2+x3+.+xn=8,则首项x1为 X1/(X1+1)=(X1+X2+...+Xn)/(X1+1+X2+3+X3+5+...+Xn+2n-1)
(-1x1/2)+(-1/2x1/3)+.+(-1/2011x1/2011)等于多少
(-1x1/2)+(-1/2x1/3)+.+(-1/2011x1/2011)等于多少