last state:很难的计算题!

来源:百度文库 编辑:查人人中国名人网 时间:2024/05/14 16:20:59
(1+1/2)*(1-1/2)*(1+1/3)*(1-1/3)*……*(1+1/9)*(1-1/9)

(帮忙详细解答。)

(1+1/2)*(1-1/2)*(1+1/3)*(1-1/3)*……*(1+1/9)*(1-1/9)
=3/2×1/2×4/3×2/3×……×10/9×8/9
=1/2×3/2×2/3×4/3×……×8/9×10/9
=1/2×10/9
=5/9