1/3 + 1/5 + 1/7 + 1/9 + 1/11 + 1/33 + 1/35 + 1/45 + 1/55 + 1
3/1+5/1+7/1+11/1+33/1+35/1+45/1+55/1+77/1=?(/表示分数线)
(1/3+1/5+1/7+1/9)*(1/5+1/7+1/9+1/11)-(1/3+1/11+1/5+1/7+1/9)*
1+1/15+3+1/35+5+1/63+7+1/99+9+1/143+11+1/195=?
(1+1/15)+(3+1/35)+(5+1/63)+(7+1/99)+(9+1/143)+(11+1/195)
简算:1/1*3+1/3*5+1/5*7+1/7*9+1/9*11
(1/5+1/7+1/9+1/11)*(1/7+1/9+1/11+1/13)-(1/5+1/7+1/9+1/11+1/1
1/1*3+1/5*7+ 1/9*11+.1/(2n-1)(2n+1)
1/3+1/5+1/7+1/9+1/11+1/13+1/15=
计算:1/3*5+1/5*7+1/7*9+1/9*11+1/11*13
(1-1/3)×(1-1/5)×(1-1/7)×(1-1/9)×(1-1/11))×(1-1/13)×(1-1/15)=
(1/2+1/3+1/4+1/5+1/6+1/7+1/8+1/9+1/10+1/11+1/12+1/13+1/14+1/
1×3/1+3×5/1+5×7/1+7×9/1+9×11/1+11×13/1简便运算