1+2+3+4+5+6+7+8+9................+1000000000-a=1000000000+a
a=?
I don't know!!!
2007-07-13 10:33 pm
回答 (2)
2007-07-13 10:43 pm
✔ 最佳答案
1+2+3+4+5+6+7+8+9................+1000000000-a=1000000000+a1+2+3+4+5+6+7+8+9................+1000000000=2a+1000000000
1+2+3+4+5+6+7+8+9................+999999999=2a
(1+999999999)x999999999/2=2a
1000000000x999999999/4=a
a=999999999000000000/4
a=249999999850000000
2007-07-13 10:45 pm
1+2+3+4+5+6+7+8+9................+1000000000-a=1000000000+a
1+2+3+4+5+6+7+8+9................+999999999=2a
(1+999999999)(999999999)/2=2a
a=1000000000x999999999/4=249999999750000000
1+2+3+4+5+6+7+8+9................+999999999=2a
(1+999999999)(999999999)/2=2a
a=1000000000x999999999/4=249999999750000000
收錄日期: 2021-04-13 17:50:37
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20070713000051KK02070