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5. 2,4,8, 16,...
Recursive:
Explicit

User Chelsie
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1 Answer

1 vote

Answer:

Recursive:
x_n=2(x_(n-1))

Explicit:
x_n=2(2)^(n-1)

Explanation:

First, note that this is a geometric sequence. This is because each term is 2 times its previous term.

The standard recursive form for a geometric sequence is:


x_n=r(x_(n-1))

Where n is the nth term, so n-1 is the previous term, and r is the common ratio.

Substitute 2 for r.

Therefore, our recursive formula is:


x_n=2(x_(n-1))

The standard form of the explicit formula for geometric sequences is:


x_n=ar^(n-1)

Again, r is the common ratio and a is the initial term.

The common ratio is 2 and the initial term is 2. So, substitute:


x_n=2(2)^(n-1)

And that's our explicit formula.

And we're done!

User Compostus
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