3/7, 5/8, 5/9, 8/11, 7/11, ()
来源:百度知道 编辑:UC知道 时间:2024/06/08 09:12:25
A.11/14 B.10/13 C.15/17 D.11/12
3/7 5/8 5/9 8/11 7/11 (11/14)
奇数项:分母为7,9,11,13,15......比前一项大2;
分子为3,5,7,9,11......比前一项大2;
偶数项:分母为8,11,14,17,20......比前一项大3;
分子为5,8,11,14,17......比前一项大3;
所以,3/7 ,5/8, 5/9, 8/11, 7/11, 11/14,9/13,14/17......
A11/14
0,1/3,1/2,3/5,2/3,5/7,( )
0 ,1/3, 1/2, 3/5, 2/3, 5/7 ()
3/7,5/8,5/9,8/11,7/11,()
3/7 、5/8、 5/9、 8/11、 7/11、 ( )
1/(2/3)/(3/4)/(4/5)/(5/6)/(6/7)/(7/8)
3/4*( )=2/7*( )=( )+3/5=( )-3/7
0,3/4,2/5,5/6,4/7,7/8,2/3
1/3+ 3/5+5/7+7/9+9/11....+1999/2001
1/(3*5)+1/(5*7)+1/(7*9)+----+1/(1997*1999)
找规律:2/4 3/6 5/8 7/9 ()/() ()/()