(1+1/1*3)*(1+1/2*4)*(1+1/3*5)*.*(1+1/11*13)具体计算过程

(1+1/1*3)*(1+1/2*4)*(1+1/3*5)*.*(1+1/11*13)具体计算过程
(1+1/1*3)*(1+1/2*4)*(1+1/3*5)*.*(1+1/11*13)具体计算过程

(1+1/1*3)*(1+1/2*4)*(1+1/3*5)*.*(1+1/11*13)具体计算过程
可以先假定任意一项为 1+1/[n(n+2)],可以将该项变换为 1+1/[n(n+2)] = [n(n+2)+1]/[n(n+2)] = (n^2=2n+1)/[n(n+2)] = (n+1)^2/[n(n+2)]；这样,就可以得到：
原式 = 2^2/(1x3)x3^2/(2x4)x4^2/(3x5)x...x12^2/(11x13) = 2/1x12/13 = 24/13.
中间的分子分母抵消过程,自己写出来就清楚了.