Question

How to write explicit formula -23,-29,-35,-41

Answer 1

The explicit formula of an arithmetic sequence is given by the following model:

$a_n=a_1+(n-1)d$

Where an is the nth term, a1 is the first term and d is the common difference.

The common difference can be calculated by subtracting one term by the term before:

$\begin{gathered} d=-29-(-23) \\ d=-29+23 \\ d=-6 \end{gathered}$

The first term is -23, so the explicit formula is:

$a_n=-23-6(n-1)$