Question

Find an equation for the nth term of the arithmetic sequence.

8, 6, 4, 2, ...

Answer 1

so what is happening here?

Answer 2

what is the change from 8 to 6?

Answer 3

These are my answer choices. I've worked the problem and I can't get any of them.

Answer 4

-2

Answer 5

ok, so if we call 8 \(a_0\) that makes six, \(a_1\)

Answer 6

so we first have 8-2

Answer 7

now how to go from 8 to 4?

Answer 8

Oh okay, that makes sense. I was making 8 a1 instead of a0.

Answer 9

well, the last answer works for 8 being a_1

Answer 10

and the first answer works for it being a_0

Answer 11

So with the first answer to get 4 we would do 8+ -2(3) = 2 so that wouldn't be correct?

Answer 12

well with the first answer 4 is a_2

Answer 13

with the last, 4 is a_3

Answer 14

Okay so that would make it 8 + -2(2) = 4 for the first?

Answer 15

yea, and the last works if you start with 8=a_1.

Answer 16

So that would make the last one the answer then? Do you have to start with 8 = a1?

Answer 17

no, they start both ways, so it depends on how you define your sequences in class. Do you start with a0 or a1?

Answer 18

a1 I believe.

Answer 19

alright, so, plug in n=1 make sure you get 8, n=2 make sure you get 6 etc. which eq. satisfies this?

Answer 20

although I would argue with the teacher if you get it incorrect. They did not specify which to begin with.

Answer 21

8 + -2(1-1) = 8
8 + -2(1-2) = 6
8 + -2(3-1) = 4

Answer 22

So would that mean the last one is correct? Also, it's for an online class and it usually isn't always specific which makes things difficult.

Answer 23

I would think so. And online classes do suck for this.

Answer 24

Yeah it does. Thank you for all your help though and for replying so quick!

Answer 25

I think most start the sequence with a1, so I'm like 95% confident.
np best of luck