(4+7+10+ ...+28)\9-(2+5+8+...+26)\9
来源:学生作业帮 编辑:搜搜做题作业网作业帮 分类:数学作业 时间:2024/07/08 21:51:14
(4+7+10+ ...+28)\9-(2+5+8+...+26)\9
![(4+7+10+ ...+28)\9-(2+5+8+...+26)\9](/uploads/image/z/19155226-58-6.jpg?t=%EF%BC%884%2B7%2B10%2B+...%2B28%29%5C9-%282%2B5%2B8%2B...%2B26%29%5C9)
(4+7+10+ ...+28)÷9-(2+5+8+...+26)÷9
=(4-2+7-5+10-8+……+28-26)÷9
=2×9÷9(这里的9表示一共有9项)
=2
=(4-2+7-5+10-8+……+28-26)÷9
=2×9÷9(这里的9表示一共有9项)
=2
1+2+3-4+5+6+7-8+9+10+11-12+.+25+26+27-28
1+2+3-4+5+6+7-8+9+10+11-12+.+25+26+27-28这条题用等差数列怎么做
1+2+3-4+5+6+7-8+9+10+11-12+13+14+15-16.+25+26+27-28
1+2+3-4+5+6+7-8+9+10+11-12+···+25+26+27-28=?
1+2+3-4+5+6+7-8+9+10+11-12……+25+26+27-28
1+2+3-4+5+6+7-8+9+10+11-12+.+25+26+27-28=?
1+2+3-4+5+6+7-8+9+10+11-12+.+25+26+27-28用简便方法计算
1+2-3-4+5+6-7-8+9+...+26-27-28+29=?
1+2+3-4+5+6+7-8+9+……+25+26+27-28=
1 3 6 10 15 21 28 2 5 9 14 20 27 4 8 13 19 26 7 12 18 25 11
1 2 5 10 17 26 4 3 6 11 18 27 9 8 7 12 19 28 16 15 14 13 20
求一数列的通项公式1,2,3,4,5,6,7,8,9,10,12,14,16,18,20,22,24,26,28,30,