:(1-1/2^2)(1-1/3^2)(1-1/4^2)L(1-1/9^2)(1-1/10^2)L(1-1/n^2)
=(1-1/2)(1+1/2)(1-1/3)(1+1/3)...(1-1/n)(1+1/n)
=1/2x3/2x2/3x4/3x..x(n-1)/mx(n+1)/n
=1/2x(n+1)/n
=(n+1)/2n
如追加其它问题,采纳本题后点击想我求助,
:(1-1/2^2)(1-1/3^2)(1-1/4^2)L(1-1/9^2)(1-1/10^2)L(1-1/n^2)
=(1-1/2)(1+1/2)(1-1/3)(1+1/3)...(1-1/n)(1+1/n)
=1/2x3/2x2/3x4/3x..x(n-1)/mx(n+1)/n
=1/2x(n+1)/n
=(n+1)/2n
如追加其它问题,采纳本题后点击想我求助,