Question

What are the explicit equation and domain for an arithmetic sequence with a first term of 5 and a second term 3?
A. An = 5-3(n-1); all integers where n≥1
B. An = 5-3(n-1); all integers where n≥0
C. An = 5-2(n-1); all integers where n≥0
D. An = 5-2(n-1); all integers where n≥1

Answer 1

@omarbirjas do you know what the answer is or do you know how to solve it?

Answer 2

any arithmetic sequence can be written as
\[A_n=A+(n-1)d\]
where A is the first term and d is common difference

Answer 3

to find d all you do is
next term-previous term

Answer 4

in this case
3-5=-2
d=-2

Answer 5

first term you have it
it is 5

Answer 6

now do the rest, in fact i did give everything lol

Answer 7

so it would be An= 5 +(n-1) -2

Answer 8

yes

Answer 9

I think the is answer A? is that right?

Answer 10

no

Answer 11

darn it

Answer 12

that does not match A

Answer 13

wait no it has to be D because of the -2

Answer 14

well the way you wrote and the way d is written are the same
they just moved -2 from instead
C could be the answer according to your line of reasoning
because c has -2 as well

Answer 15

so what determines the correct answer is that condition tied to it
n>=1 for d and n>=0 for c
which is correct for our case
for the first term to be 5

Answer 16

so the n≥1 is wrong

Answer 17

it is d
because if it is c
the first term would have been 7 not 5

Answer 18

it is d
because when you play n=1
for the first term what you get is A1=5-2(1-1)=5-0=5

Answer 19

plug* i meant not play

Answer 20

I'm sorry I was confused! Thank you so much! This helped me a lot!

Answer 21

no problem