2/5+2/35+2/63+2/99+ +2/483 = ?
2/5+2/35+2/63+2/99+: +2/483
x-2/15-2/35-2/63-2/99-2/143-2/195=7/15
2/3+2/15+2/35+2/63+2/99=
2/3+2/15+2/35+2/63+2/99
2/3+2/15+2/35+2/63+2/99
2/15 + 2/35 + 2/63 + 2/99 + .... + 2/575 + 2/675
2/3+2/15+2/35+2/63+2/99+2/143+2/195
viết tiếp vào dấu chấm: 2/15 ; 2/35 ; 2/63 ; 2/99 ; ....... .