Exercise 1 Page 63

Explicit equations for arithmetic sequences follow a specific format. In this form, $a_1$ is the first term in a given sequence, $d$ is the common difference from one term to the next, and $a_n$ is the $n\text{th}$ term in the sequence. For this exercise, the first term is $a_1=3.$ Let's observe the other terms to determine the common difference $d.$