Question

A recursive rule for an arithmetic sequence is a1=−3;an=an-1+7

What is the iterative rule for this sequence?

Answer 1

C is the answer. Hope you get a good grade

Answer 2

`a_(n)=7n-10`

Explanation:

Givens

`a_(1)=-3\\a_(n)=a_(n-1) +7`

The formula to find the iterative rule of an arithmetic sequence is

`a_(n)=a_(1)+(n-1)d`

Where
`d=7` and
`a_(1)=-3`, replacing these values, we have

`a_(n)=-3+(n-1)7\\ a_(n)=7n-7-3\\ a_(n)=7n-10`

Therefore, the right answer is the first choice:
`a_(n)=7n-10`