(1+1/2)+(2+1/22)+(3+1/23)+.+(n+1/2的n次方)等于多少

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(1+1/2)+(2+1/22)+(3+1/23)+.+(n+1/2的n次方)等于多少
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(1+1/2)+(2+1/22)+(3+1/23)+.+(n+1/2的n次方)等于多少
(1+1/2)+(2+1/22)+(3+1/23)+.+(n+1/2的n次方)等于多少

(1+1/2)+(2+1/22)+(3+1/23)+.+(n+1/2的n次方)等于多少
=1+2+.+n+(1/2+1/2^2+1/2^3+.1/2^n)
=n(n+1)/2+1/2(1-1/2^n)/(1-1/2)
=n(n+1)/2+1-1/2^n

楼上是对的,就是一个等差数列(1+2+3+...+n)和一个等比数列(1/2,1/2^2,1/2^3,....1/2^n)的求和;
等差数列Sn=n(a1+an)/2=n(1+n)/2;
等比数列Sn=[A1(1-q^n)]/(1-q)=[1/2(1-1/2^n)]/(1-1/2)