Given the nth term for this arithmetic sequence, how to find the common difference and the first four terms too? $a_n$ = 3n - 2

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Answer 1 · 2018-07-06T12:24:00

The first four terms are
$a_1=1$
$a_2=4$
$a_3=7$
$a_4=10$

Common difference is
$d=3$

$a_n=3n-2$
$n=1$

$a_1=3x1-2=3-2=1$
$n=2$
$a_2=3x2-2=6-2=4$
$n=3$
$a_3=3x3-2=9-2=7$
$n=4$
$a_4=3x4-2=12-2=10$

The first four terms are
$a_1=1$
$a_2=4$
$a_3=7$
$a_4=10$
Common difference is
$a_2-a_1=4-1=3$
$a_3-a_2=7-4=3$
$a_4-a_3=10-7=3$

$d=3$

Given the nth term for this arithmetic sequence, how to find the common difference and the first four terms too? a_na_n = 3n - 2