Question

Write this series in summation form.
9 + 18 + 27 + 36 + 45

Answer 1

Each term is how much more than the last one?

Answer 2

9

Answer 3

Ok, so now we just plug in that to the formula for an arithmetic series..

\[\sum_{n=1}^{t}n(d)\]

Where d is the difference between each term and the proceeding one, and t is the number of terms you want to have.

Answer 4

what does the n-1 mean and do in this type of equation

Answer 5

I don't have an n-1.

Answer 6

But if I did, it would subtract 1 from n.

Answer 7

on the bottom of the greek letter s?

Answer 8

it says n-1

Answer 9

No, it says n = 1