Question

An arithmetic series in sigma notation is shown. What is the sum of the first 14 terms of the series

Answer 1

-298

Explanation:

Given the relation above :

n = 1 through 14

For n = 1

22 - 6(1)

n = 2

22- 6(2)....

Hence, sun of first 14 terms :

(22 - 6*1) + (22 + 6*2) + (22 - 6*3) + (22 - 6*4) + (22 - 6*5) + (22 - 6*6) + (22 - 6*7) + (22 - 6*8) + (22 - 6*9) + (22 - 6*10) + (22 - 6*11) + (22 - 6*12) + (22 - 6*13) + (22 - 6*14)

= - 298