If the nth partial sum of the sequence an is given by

n

Sigma 2k+4

k=1

Then what is the nth term of the sequence?

A. 6

B. 2n+4

C. 6+8+10+12 + ... + (2n+4)

D. 2 (1) + 4+2 (n) + 4

This is an example of a series in arithmetic progression.

The nth term an can be calculated using the formula:

an = a1 + (n - 1) d

where: a1 = is the 1st term of the series

d = common difference

Calculating for the 1st term:

a1 = 2k + 4 = 2 (1) + 4 = 6

Calculating for the common difference by:

d = a2 - a1

d = 2 (2) + 4 - 6

d = 2

Therefore calculating for an:

an = 6 + (n - 1) 2

an = 6 + 2n - 2

an = 2n + 4

Therefore the answer is B. 2n+4