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How do you find the explicit formula for the following sequence 2, 4, 6, 8,...?

1 Answer

Psykolord1989 .

Nov 23, 2017

$a_{n} = a_{1} + 2 (n - 1) = 2 + 2 (n - 1)$ $a_n = a_1+2(n-1) = 2+2(n-1)$

Explanation:

Each term is 2 greater than the term before it. Thus for any given term, $a_{n}$ $a_n$ , our equation is:

$a_{n} = 2 n$ $a_n = 2n$

We can write this in a form closer to standard, by noting that $a_{1} = 2$ $a_1=2$ , so we can make it dependent on $a_{1}$ $a_1$ ..

$a_{n} = a_{1} + 2 (n - 1) = 2 + 2 (n - 1)$ $a_n = a_1+2(n-1) = 2+2(n-1)$

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