1/3+1/6+1/10+1/15+1/21+1/28+1/36+1/45+1/55+1/66+1/78+1/91
来源:学生作业帮 编辑:大师作文网作业帮 分类:数学作业 时间:2024/09/29 19:25:48
1/3+1/6+1/10+1/15+1/21+1/28+1/36+1/45+1/55+1/66+1/78+1/91
设原式的和为S,再把原式乘以1/2得:
1/2S=1/2*(1/3+1/6+1/10+1/15+……+1/78+1/91)
1/2S=1/6+1/12+1/20+1/30+1/42+……+1/156+1/182
1/2S=1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+……+1/12-1/13+1/13-1/14
1/2S=1/2-1/14
1/2S=6/14
两边乘以2得:S=6/7
望你进步!qq:1209538287
1/2S=1/2*(1/3+1/6+1/10+1/15+……+1/78+1/91)
1/2S=1/6+1/12+1/20+1/30+1/42+……+1/156+1/182
1/2S=1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+……+1/12-1/13+1/13-1/14
1/2S=1/2-1/14
1/2S=6/14
两边乘以2得:S=6/7
望你进步!qq:1209538287
1\3+1\6+1\10+1\15+1\21+1\28+1\36+1\45+1\55+1\66+1\78+1\91+1\
1/3+1/6+1/10+1/15+1/21+1/28+1/36+1/45+1/55+1/66+1/78+1/91
计算:1/3+1/6+1/10+1/15+1/21+1/28+1/36+1/45+1/55+1/66+q/78+1/91
1/3+1/6+1/10+1/15+1/21+1/28+1/36+1/45+1/55+1/66
1+1/3+1/6+1/10+1/15+1/21+1/28+1/36+1/45+1/55+1/66+.+1/202105
【急】!简便运算!(1) 1/3+1/6+1/10+1/15+1/21+1/28+1/36+1/45+1/55+1/66
1\3+1\6+1\10+1\15+1\21+1\28+1\36+1\45+1\50+1\55
1/3 + 1/6 + 1/10 + 1/15 + 1/21 + 1/28 + 1/36 + 1/45 + 1/55=?
1/3+1/8+1/10+1/15+1/21+1/28+1/36+1/45+1/55
1/3+1/6+1/10+1/15+1/21+1/28+1/36+1/45+1/50+1/55=?
奥数数学题1+1/3+1/6+1/10+1/15+1/21+1/28+1/36+1/45+1/55简便运算急~
小六计算题1+1/3+1/6+1/10+1/15+1/21+1/28+1/36+1/45+1/55=?如果把他都改成-号