1,-3,-7,-11,-15
如何计算1/(3*7)+1/(7*11)+1/(11*15)+.+1/(39*43)=
1/3*7+1/7*11+1/11*15+...+1/25*39
1+3+5+7+9+11+13+15+…+99
1,-3,5,-7,9,-11,13,-15,17
数字推理:-3,1,-7,41,-11,85,-15,(
1+3+5+9+7+11+13+15+17+19
1-3-5+7+9-11-13+15+17-.+999
1+3-5-7+9+11-13-15+...2001
1+3+5+7+9+11+13+15=
4 9 16 7 11 2 15 3 1 8
1/3,3/7,5/11,7/15,( ),( ),13/27,15/31
简便计算1/1*3*5+1/3*5*7+1/5*7*9+1/7*9*11+1/9*11*13+1/11*13*15中1/