The sum of the first n terms in a certain arithmetic sequence is given by S(adsbygoogle = window.adsbygoogle || []).push({}); _{n}= 3n^{2}- n. Show that the nth term of the sequence is given by a_{n}= 6n - 4.

so far i have done:

S_{n}= (n / 2) (a_{1}+ a_{n}) = 3n^{2}- n

i solved for a_{1}+ a_{n}= 6n - 2

i also have a_{n}= a_{1}+ d(n-1).

i don't know what do to next. please help me.

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# Homework Help: Arithmetic sequence problem

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