1x1+2x2+3x3+......................+99x99=?
回答 (2)
2007-08-02 10:00 pm
✔ 最佳答案
1x1+2x2+...+10x10=38511x11+12x12+...+20x20=2485
21x21+22x22+...+30x30=6585
31x31+32x32+...+40x40=12685
41x41+42x42+...+50x50=20785
51x51+52x52+...+60x60=30885
61x61+62x62+...+70x70=42985
71x71+72x72+...+80x80=57085
81x81+82x82+...+90x90=73185
91x91+92x92+...+99x99=81285
so,,
385+2485+6585+12685+20785+30885+42985+57085+73185+81285
=328350
參考: me
2007-07-19 7:19 am
me too
收錄日期: 2021-05-02 18:33:36
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20070718000051KK05487