1. Write down the exact sequence of the numbers you added and the sum
Answers
Answered by
10
Find the sum of the first 20 terms of the arithmetic series if a1=5 and a20=62 .
S20=20(5 + 62)2S20=670
Example 2:
Find the sum of the first 40 terms of the arithmetic sequence
2,5,8,11,14,⋯
First find the 40 th term:
a40=a1+(n−1)d =2+39(3)=119
Then find the sum:
Sn=n(a1 + an)2S40=40(2 + 119)2=2420
Answered by
5
Answer:
ok the ans in me okkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk
Attachments:
Similar questions