求lim(1-1/2^2)(1-1/3^2)……(1-1/n^2)的值

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求lim(1-1/2^2)(1-1/3^2)……(1-1/n^2)的值
求lim(1-1/2^2)(1-1/3^2)……(1-1/n^2)的值

求lim(1-1/2^2)(1-1/3^2)……(1-1/n^2)的值
(1-1/2^2)(1-1/3^2)……(1-1/n^2)
= (1-1/2)(1+1/2)(1-1/3)(1+1/3).(1+1/n)(1-1/n)
= 1/2 * 3/2 * 2/3 * 4/3 * .* (n+1)/n * (n-1)/n
= (1/2 * 2/3 * ...* (n-1)/n) * (3/2 * 4/3 * ...* (n+1)/n)
= (1/n) * ((n+1)/2)
= (n+1)/(2n)
= (1+1/n) / 2
lim (1+1/n) / 2 (n->+无穷) = 1/2

(1-1/2^2)(1-1/3^2)……(1-1/n^2)=1/2*1/n
lim(1-1/2^2)(1-1/3^2)……(1-1/n^2)=0

选a