Re: [中學] 數論
※ 引述《lilygarfield (愛情讓我變成詩人)》之銘言：
: 從
: 1/2, 1/3, 1/4, 1/5, ..., 1/99 中
: 挑出10個數，使之加總為 1
: 該挑那10個數？
利用 1/n = 1/(n+1) + 1/n(n+1)
1
= 1/2 + (1/2) [標()的表示要使用公式]
= (1/2) + (1/3) + (1/6)
= 1/3 + 1/6 + (1/4) + 1/12 + (1/7) + 1/42
= 1/3 + 1/6 + 1/5 + 1/20 + 1/12 + (1/8) + 1/56 +1/42
= 1/3 + 1/6 + 1/5 + 1/20 + 1/12 + (1/9) + 1/72 + 1/56 + 1/42
= 1/3 + 1/6 + 1/5 + 1/20 + 1/12 + 1/10 + 1/90 + 1/72 + 1/56 + 1/42
= 1/3 + 1/5 + 1/6 + 1/10 + 1/12 + 1/20 + 1/42 + 1/56 + 1/72 + 1/90 #
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