If-4a-n-2a-n-3n-2-2n-3-find-a-n-

Question Number 131158 by EDWIN88 last updated on 02/Feb/21

I f 4 a_{n} + 2 a_{- n} = 3 n^{2} + 2 n - 3

f i n d a_{n} = ?

Answered by mr W last updated on 02/Feb/21

4 a_{n} + 2 a_{- n} = 3 n^{2} + 2 n - 3

4 a_{- n} + 2 a_{n} = 3 n^{2} - 2 n - 3

8 a_{n} + 4 a_{- n} = 6 n^{2} + 4 n - 6

\Rightarrow 6 a_{n} = 3 n^{2} + 6 n - 3

\Rightarrow a_{n} = \frac{1}{2} (n^{2} + 2 n - 1)

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