早教吧作业答案频道 -->数学-->
2+12+22+32+……1000000000000000000000000002要写出祥细过程.
题目详情
2+12+22+32+……1000000000000000000000000002
要写出祥细过程.
要写出祥细过程.
▼优质解答
答案和解析
等差数列求和
和=(首项+末项)*项数/2
项数=(末项-首项)/公差+1
公差即后一项减去前一项的差,此题公差为10,所以
2+12+22+32+……+1000000000000000000000000002
=(2+1000000000000000000000000002)*100000000000000000000000001/2
=5000000000000000000000000001*1000000000000000000000000001
和=(首项+末项)*项数/2
项数=(末项-首项)/公差+1
公差即后一项减去前一项的差,此题公差为10,所以
2+12+22+32+……+1000000000000000000000000002
=(2+1000000000000000000000000002)*100000000000000000000000001/2
=5000000000000000000000000001*1000000000000000000000000001
看了 2+12+22+32+……1...的网友还看了以下:
速算与巧算(2)959595*96-969696*95444…4(2005个4)/555…5(20 2020-04-07 …
还是lingo问题road(country,country):length,xie,c;endse 2020-05-13 …
大家快来看看这几道题怎么简算!我急用!0.071*1234+0.71*567.6+7.1*23.4 2020-05-16 …
直接写出得数.0.4+4.3=4.8÷6=5.8×100=940÷100=0.24÷4=50×0. 2020-07-09 …
计算(0.1+0.12+0.123+0.1234)×(0.12+0.123+0.1234+0.12 2020-07-18 …
直接写得数.1.2+0.3=4+0.6=12.9-5=12+3.5=0.9+0.7=0.6+1.4 2020-07-19 …
口算:5.6+3.4=10-2.7=2.8+3.3=1.2×0.8=10÷2.5=8×1.25=3 2020-07-19 …
1.0.999x0.7+0.111x2.7=?2.(1+0.12+0.23)x(0.12+1.0. 2020-07-24 …
(2012•酉阳县模拟)直接写得数1-49=25-14=16×1116=0.25×12÷0.125 2020-07-25 …
一.计算题(一)直接写出得数:0.3+0.57=0.54÷6=2.2×5+9=2.4×0.5=8-0 2020-11-17 …