1/3+1/15+1/35+1/65+.+1/17*19
1个回答
1/3+1/15+1/35+1/65+.+1/17*19
=1/2(1-1/3+1/3-1/5+1/5-1/7+...+1/17-1/19)
=1/2(1-1/19)
=9/19
相关问题
1/3+1/15+1/35+.+1/323=9/19,
找规律:(1)1,1,3,7,17,41,( ) (2)65 ,35 ,17 ,3,( ) (3) 2 ,8 ,24 ,
(1+13+15+17)×(13+15+17+19)−(1+13+15+17+19)×(13+15+17).
(1+17/1)*(1+17/2)*(1+17/3)*...*(1+17/18) 之积除以 (1+19/1)*(1+19
1,9,11,15,17,19,21,27,33,35,37,41,45,49,57,65,72,81合数有,偶数有,3
1/11×13+1/13×15+1/15×17+1/17×19+1/38
计算:1.1+3.3+5.5+7.7+9.9+11.11+13.13+15.15+17.17+19.19=______.
计算:1.1+3.3+5.5+7.7+9.9+11.11+13.13+15.15+17.17+19.19=______.
计算:1.1+3.3+5.5+7.7+9.9+11.11+13.13+15.15+17.17+19.19=______.