Find an explicit rule for the nth term of the arithmetic sequence.
-$1,3,5,7 , \ldots$
A) $a _ { n } = 1 + 2$
B) $a _ { n } = 1 + 2 ( n + 1 )$
C) $a _ { n } = 1 + 2 ( n )$
D) $a _ { n } = 1 + 2 ( n - 1 )$

Question

Quizplus · Accepted Answer

The explicit rule for an arithmetic sequence is $a_n = a_1 + d(n - 1)$, where $a_1$ is the first term and $d$ is the common difference. Here, $a_1 = 1$ and $d = 2$, so the rule is $a_n = 1 + 2(n - 1)$.

Find an Explicit Rule for the Nth Term of the Arithmetic