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Can someone help idk if this is right

Can someone help idk if this is right-example-1
User Tek Yin
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1 Answer

4 votes

Answer:


a_n=-3 \cdot a_(n-1)


a_1=2

You gave the explicit form.

Explanation:

You gave the explicit form.

The recursive form is giving you a term in terms of previous terms of the sequence.

So the recursive form of a geometric sequence is
a_n=r \cdot a_(n-1) and they also give a term of the sequence; like first term is such and such number. All this says is to get a term in the sequence you just multiply previous term by the common ratio.

r is the common ratio and can found by choosing a term and dividing by the term that is right before it.

So here r=-3 since all of these say that it does:

-54/18

18/-6

-6/2

If these quotients didn't match, then it wouldn't be geometric.

Anyways the recursive form for this geometric sequence is


a_n=-3 \cdot a_(n-1)


a_1=2

User Matthew Mitchell
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5.1k points