Find the sum of a finite arithmetic sequence from n = 1 to n = 13, using the expression 3n + 3.

Question

Chace Moody

Mathematics

24 July, 04:59

Find the sum of a finite arithmetic sequence from n = 1 to n = 13, using the expression 3n + 3.

+3

Answers (2)

Know the Answer?

Wilson Wells · Answer 1

Sum of n terms = (n/2) [2a1 + (n-1) d]

Here, a1 = 3 (1) + 3 = 6, n = 13 and d = second term - first term 9-6 = 3

so sum of 13 term = 6.5 (12 + 12*3) = 312, - - - Answer

Joseph Holden · Answer 2

The sum of an arithmetic sequence is the average of the first and last terms time the number of terms ...

So the first term is 3+3 and the last term is 3 (13) + 3

So the sum is:

13 (6+42) / 2

312