我係1個中三生......有條問題我想問好耐,我問maths ar sir都答5到我:
條問題係:
把下列各題轉做a分之b..其中a,b係整數.(係有理數和無理數ge問題)
x=0.9999(this係循環小數)
10x=9.9999
9x=9
x=1
明明一開頭x=0.9999,why最後x=1 ????
有冇人可以答下我ar
maths.........10marks
2007-11-13 3:19 am
回答 (2)
2007-11-13 7:13 am
✔ 最佳答案
Let x=0.9999 (4 sig. figure)10x=9.9990
9x=8.9991 (not equal to 9)
x=0.9999 (not equal to 1)
As you can see, when
x=0.9999...............9999
10x=9.9999...............9990
9x=8.9999...............9991 (not equal to 9)
Therefore, x is not equal to 1
參考: me
收錄日期: 2021-04-13 14:26:10
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20071112000051KK02927