Question

What is the explicit formula for this sequence? −8, −3, 2, 7, …

Answer 1

It's an arithmetical sequence with
`a_1=-8,d=5`

So

`a_n=a_1+(n-1)d\\\\a_n=-8+(n-1)\cdot5\\\\a_n=-8+5n-5\\\\\boxed{a_n=5n-13}`