Find a formula for a_n for the arithmetic sequence. A₁ = 7, d = -8 A) $a _ { n } = 7 \left( - \frac { 1 } { 8 } \right) ^ { n - 1 }$ B) $a _ { n } = - 8 + 7 ( n - 1 )$ C) $a _ { n } = 7 - 9 n$ D) $a _ { n } = 15 - 8 n$ E) $a _ { n } = 7 - 8 ^ { n - 1 }$

Question

Quizplus · Accepted Answer

The formula for the nth term of an arithmetic sequence is $a_n = a_1 + (n - 1)d$, where $a_1$ is the first term and $d$ is the common difference. Given $a_1 = 7$ and $d = -8$, substituting these values gives $a_n = 7 + (n - 1)(-8) = 7 - 8n + 8 = 15 - 8n$.

Find a Formula for An for the Arithmetic Sequence an=7(−18)n−1a _ { n } = 7 \left( - \frac { 1 } { 8 } \right) ^ { n - 1 }an​=7(−81​)n−1

Find a Formula for A_n for the Arithmetic Sequence $a _ { n } = 7 \left( - \frac { 1 } { 8 } \right) ^ { n - 1 }$