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來源: 於 2009-04-08 13:41:44 [博客] [舊帖] [給我悄悄話] 本文已被閱讀：次

NO 1.
(1/9)*9=1
1/9=0.111111....
0.111111....*9=0.999999....=(1/9)*9=1

No.2

(2/3)+(1/3)=1
0.666666...+0.333333...=0.999999....=1

No.3

(1/3)*3=1
0.333333....*3=0.999999....=1