Question

Given the geometric sequence where a1 = 3 and the common ratio is −1, what is the domain for n?

All integers where ≤ 0
All integers where n ≥ 0
All integers where n ≤ 1
All integers where n ≥ 1

Answer 1

@jim_thompson5910

Answer 2

i got C:)

Answer 3

The domain of any arithmetic or geometric sequence is \(\Large n > 0\) or \(\Large n \ge 1\) where n is an integer. The reason why is because n is a counting number which indexes the terms

n = 1 refers to the first term
n = 2 to the second term
n = 3 is the third term
etc

Answer 4

then that narrows it down to b or d

Answer 5

So then, the answer would be B. Right?

Answer 6

it's NOT b because \(\Large n \ge 0\) includes n = 0

but we don't start with n = 0. We start with n = 1

Answer 7

Oh so 0 isn't a natural #?

Answer 8

nope

Answer 9

Ok. I get it now:) Thanks!

Answer 10

natural numbers = counting numbers

counting numbers = 1,2,3,4,...

Answer 11

Oh! Yeah that's true! You dont start w/ ero when you count:)

Answer 12

yeah and when you say "first term" it's natural to think of 1 as the first thing

if you made 0 first, then 1 would be second. That's a bit confusing

Answer 13

Hm I didn't think of it like that! But yeah, that's true