Question

What is the sum of the arithmetic sequence 3, 9, 15…, if there are 34 terms?

Answer 1

so what is the answer

Answer 2

ok

Answer 3

these are the only aswers you can choose from

3,072

3,468

4,242

4,486

Answer 4

so im guessing number two is the best bet

Answer 5

d=6
a=3

\[\ S _{n} = \frac{n}{2}[2a+(n-1)d] \]\[\ S_{n}=\frac{34}{2}[2(3)+(34-1) \times 6] \]\[\ S_{n}=17[6+33 \times 6] \]

Answer 6

^^sasogeek has the better explanation
i guess I got too caught up in calculus ro figue out a simpler way

Answer 7

*to figure (darn keyboard)

Answer 8

I'm deleting my past answers to avoid confusion.

Answer 9

\[\ S_n=3468 \]