通辽信息港招聘求职r:1-5/6+7/12-9/20+11/30-13/42+15/56-17/72简便方法怎么算
来源:百度文库 编辑:查人人中国名人网 时间:2024/07/07 08:59:08
。。。。。帮帮我
Note:5/6 = (2+3)/ ( 2*3 )= 1/2 + 1/3
1-5/6+7/12-9/20+11/30-13/42+15/56-17/72
= 1 - 1/2 - 1/3 + 1/3 + 1/4 - 1/4 - 1/5 ……+1/8
- 1/8 - 1/9
= 1 - 1/2 - 1/9
= 18/18 - 9/18 - 1/18
= 8/18
= 4/9
= 0.44444444444444444444444444444444444
=1-(2+3)/(2*3)+(3+4)/(3*4)-(4+5)/(4*5)+(5+6)/(5*6)-(6+7)/(6*7)+(7+8)/(7*8)-(8+9)/(8*9)
=1-2/(2*3)-3/(2*3)+3/(3*4)+4/(3*4)-4/(4*5)-5/(4*5)+5/(5*6)+6/(5*6)-6/(6*7)-7/(6*7)+7/(7*8)+8/(7*8)-8/(8*9)-9/(8*9)
=1-1/3-1/2+1/4+1/3-1/5-1/4+1/6+1/5-1/7-1/6+1/8+1/7-1/9-1/8
=1-1/2-1/9
=7/18
1/2,5/6,7/12,9/20,?后一个是什么?为什么 ?谢谢
1/2 5/6 7/12 9/20 ( ) 后一个是什么?为什么 ?谢谢
1-5/6+7/12-9/20+11/30-13/42+15/56-17/72简便方法怎么算
1-5/6+7/12-9/20+11/30-13/42+15/56-17/72简便方法怎么算
1/5×1/6+1/6×1/7+1/7×1/8+1/8×1/9+1/9×1/10的简便方法是什么?
1/2+1/3+1/4+1/5+1/6+1/7+1/8+1/9+1/10+1/11+1/12+1/13……(一直按规律加到)1/2000
1/2+3/4+5/6+7/8+9/10+``````+99/100=?
1 8 9 4 1 1/6的排列规律、0 3/2 2/3 5/4 4/5 7/6
简便计算:5/6-7/12+9/20-11/30+13/42-15/56+17/72-19/90
按规律填数:1/3,1/2,5/9,7/12,3/5,11/18