1+19/6+61/12+141/20+271/30+463/42+729/56+1081/72+1531/90=
来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/10/05 05:10:55
1+19/6+61/12+141/20+271/30+463/42+729/56+1081/72+1531/90=
”/”是分数线
请写解题思路
”/”是分数线
请写解题思路
1+19/6+61/12+141/20+271/30+463/42+729/56+1081/72+1531/90
=1+(3+1/6)+(5+1/12)+(7+1/20)+(9+1/30)+(11+1/42)+(13+1/56)+(15+1/72)+(17+1/90)
=(1+3+5+7+9+11+13+15+17) +1/(2*3)+1/(3*4)+1/(4*5)+1/(5*6)+1/(6*7)+1/(7*8)+1/(8*9)+1/(9*10)
=(1+17)*9/2 +(1/2-1/3)+(1/3-1/4)+(1/4-1/5)+(1/5-1/6)+(1/6-1/7)+(1/7-1/8)+(1/8-1/9)+(1/9-1/10)
=81+1/2-1/10
=81又2/5
=1+(3+1/6)+(5+1/12)+(7+1/20)+(9+1/30)+(11+1/42)+(13+1/56)+(15+1/72)+(17+1/90)
=(1+3+5+7+9+11+13+15+17) +1/(2*3)+1/(3*4)+1/(4*5)+1/(5*6)+1/(6*7)+1/(7*8)+1/(8*9)+1/(9*10)
=(1+17)*9/2 +(1/2-1/3)+(1/3-1/4)+(1/4-1/5)+(1/5-1/6)+(1/6-1/7)+(1/7-1/8)+(1/8-1/9)+(1/9-1/10)
=81+1/2-1/10
=81又2/5
1+19/6+61/12+141/20+271/30+463/42 计算
1+1/2-5/6+7/12-9/20+11/30-13/42+15/56-17/72+19/90
5/6-7/12+9/20-11/30+13/42-15/56+17/72-19/90=
1-5/6+7/12-9/20-11/30-13/42+15/56-17/72+19/90
1-5/6+7/12-9/20+11/30-13/42+15/56-17/72+19/90 简便计算
1-5/6+7/12-9/20+11/30-13/42+15/56-17/72+19/90
1-6/5+12/7-20/9+30/11-42/13+56/15-72/17+90/19简算
1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90=
1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90=多少
1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90=______
2分之1+6分之5+12分之11+20分之19+30分之29+42分之41+56分之55+72分之71+90分之89=?
1-6分之5+12分之7-20分之9+30分之11-42分之13+56分之15-72分之17+90分之19=?