求Sn=1 (1/2)+3 (1/2)²+5 (1/2)³+...+(2n-1) (1/2)n次方 计算

问题描述:

求Sn=1 (1/2)+3 (1/2)²+5 (1/2)³+...+(2n-1) (1/2)n次方 计算

Sn=1 (1/2)+3 (1/2)^²+5 (1/2)^³+...+(2n-1) (1/2)^n1/2*Sn= 1 (1/2)^²+3 (1/2)^³+...+(2n-3) (1/2)n+(2n-1) (1/2)^(n+1)上式减下式:1/2*Sn=1/2+2[(1/2)^2+(1/2)^3+……+(1/2)^n]-(2...