[問卦] 為什麼0.99999…等於1?
https://www.ptt.cc/bbs/Gossiping/M.1780719626.A.8BE.html

Re: [問卦] 為什麼0.99999…等於1?
https://www.ptt.cc/bbs/Gossiping/M.1780720538.A.08B.html

Re: [問卦] 為什麼0.99999…等於1?
https://www.ptt.cc/bbs/Gossiping/M.1780721410.A.4BC.html

Re: [問卦] 為什麼0.99999…等於1?
https://www.ptt.cc/bbs/Gossiping/M.1780735333.A.474.html