(1-1⼀2)*(1+1⼀2)*(1-1⼀3)*(1+1⼀3)*……*(1-1⼀99)*(1+1⼀99)。

2025-12-17 19:44:57
推荐回答(4个)
回答1:

(1 - 1/2)*(1 + 1/2) = (1*3)/(2*2)
(1 - 1/3)*(1 + 1/3) = (2*4)/(3*3)
(1 - 1/4)*(1 + 1/4) = (3*5)/(4*4)
(1 - 1/5)*(1 + 1/5) = (4*6)/(5*5)
..................................
(1 - 1/98)*(1 + 1/98) = (97*99)/(98*98)
(1 - 1/99)*(1 + 1/99) = (98*100)/(99*99)

原式 = (98! * 100! / 2)/(99!)^2 = 1/99*100/2 = 50/99
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哇!原来不分解啊,哈哈哈,一楼绝妙!

回答2:

(1-1/2)*(1+1/2)*(1-1/3)*(1+1/3)*……*(1-1/99)*(1+1/99)
=(1/2)*(3/2)*(2/3)*(4/3)*(3/4)*……*(98/99)*(100/99)
=(1/2)*(100/99)
=50/99

回答3:

50/99

回答4:

经典的问题
规律的解答