Question

Please help me!

1. What is the sum of the arithmetic sequence 4, 11, 18 …, if there are 26 terms?

a. 2470
b.2379
c.1534
d.1482

Answer 1

\[\Large \frac{n(A_1 + A_n)}{2}\] that's the equation if i remember it right

Answer 2

so what is your n, A_1 and A_n?

Answer 3

I'm lost. is n 26

Answer 4

yeah..find A_26 first to make it easier \[A_{26} = A_1 (n - 1)d\]

Answer 5

How do i find it? I don't understand this at all. i'm sorry

Answer 6

\(A_1\) is the first term of the series

n is the number of terms in the series

to find use \(d = A_2 - A_1\)

Answer 7

to find d*

Answer 8

I figure out the answer thank you..