1+3 6/1+5 12/1+7 20/1+9 30/1+11 42/1+13 56/1+15 72/1+17 90/1
来源:学生作业帮 编辑:百度作业网作业帮 分类:数学作业 时间:2024/07/08 20:33:02
1+3 6/1+5 12/1+7 20/1+9 30/1+11 42/1+13 56/1+15 72/1+17 90/1+19 110/1
这个怎么巧算
这个怎么巧算
![1+3 6/1+5 12/1+7 20/1+9 30/1+11 42/1+13 56/1+15 72/1+17 90/1](/uploads/image/z/1342964-20-4.jpg?t=1%2B3+6%2F1%2B5+12%2F1%2B7+20%2F1%2B9+30%2F1%2B11+42%2F1%2B13+56%2F1%2B15+72%2F1%2B17+90%2F1)
1+3 6/1+5 12/1+7 20/1+9 30/1+11 42/1+13 56/1+15 72/1+17 90/1+19 110/1
=(1+3+5+7+9+11+13+15+17+19)+(1/6+1/12+1/20+-----+1/110)
=100+(1/2-1/3+1/3-1/4+1/4-1/5+-----+1/10-1/11)
=100+(1/2-1/11)
=100+9/22
=100又9/22
=(1+3+5+7+9+11+13+15+17+19)+(1/6+1/12+1/20+-----+1/110)
=100+(1/2-1/3+1/3-1/4+1/4-1/5+-----+1/10-1/11)
=100+(1/2-1/11)
=100+9/22
=100又9/22
1+3 6/1+5 12/1+7 20/1+9 30/1+11 42/1+13 56/1+15 72/1+17 90/1
1+1/2-5/6+7/12-9/20+11/30-13/42+15/56-17/72+19/90
计算1-【5/6】+【7/12】-【9/20】+【11/30】-【13/42】+【15/56】-【17/72】
-1+5/6-7/12+9/20-11/30+13/42-15/56+17/72
1-5\6+7\12-9/20+11/30-13/42+15/56-17/72
1又1/3-7/12+9/20-11/30+13/42-15/56+17/72
1+3又1/6+5又1/12+7又1/20+9又1/30+11又1/42+13又1/56+15又1/72+17又1/90
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又1/3-7/12+9/20-11/30+13/42-15/56+17/72-19/90