Write the first n terms of the given arithmetic sequence (the value of n is indicated in the question).
-3, 9, 15, 21, 27, . . .
A) $a _ { n } = 3 n - 6 ; a _ { 6 } = 12$
B) $a _ { n } = 6 n - 1 ; a _ { 6 } = 35$
C) $a _ { n } = 3 ( 2 n - 1 ) ; a _ { 6 } = 33$
D) $a _ { n } = 3 ( 6 ) ^ { n - 1 } ; a _ { 6 } = 18$

Question

Write the first n terms of the given arithmetic sequence (the value of n is indicated in the question).
-3, 9, 15, 21, 27, . . . 
A) $a _ { n } = 3 n - 6 ; a _ { 6 } = 12$
B) $a _ { n } = 6 n - 1 ; a _ { 6 } = 35$
C) $a _ { n } = 3 ( 2 n - 1 ) ; a _ { 6 } = 33$
D) $a _ { n } = 3 ( 6 ) ^ { n - 1 } ; a _ { 6 } = 18$

Quizplus · Accepted Answer

The given sequence is an arithmetic sequence with a common difference of 6. The nth term formula for an arithmetic sequence is $a_n = a_1 + (n - 1)d$, where $a_1$ is the first term and $d$ is the common difference. For this sequence, $a_1 = 3$ and $d = 6$, so $a_n = 3 + (n - 1)6 = 3 + 6n - 6 = 6n - 3$, which simplifies to $3(2n - 1)$. For $n = 6$, $a_6 = 3(2*6 - 1) = 3*11 = 33$.

Write the First N Terms of the Given Arithmetic Sequence an=3n−6;a6=12a _ { n } = 3 n - 6 ; a _ { 6 } = 12an​=3n−6;a6​=12

Write the First N Terms of the Given Arithmetic Sequence $a _ { n } = 3 n - 6 ; a _ { 6 } = 12$