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4 years ago

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A recursive rule for a geometric sequence is a1=49;an=3an−1 . What is the explicit rule for this sequence? Enter your answer in

the box. an=

2 answers:

faltersainse [42]4 years ago

6 0

Answer:

an= 4/9(3^n-1)

Step-by-step explanation:

Just took the test and passed with this answer. For future students looking. I am 100% correct on this. :)

Georgia [21]4 years ago

4 0

Answer :

Explicit rule is

$a_n=49(3)^{n-1}$

Step-by-step explanation:

A recursive rule for a geometric sequence is a1=49;an=3an−1

First term a1= 49

$a_2= 3 * a_1= 3*49= 147$

$a_2= 3 * a_2= 3*147= 441$

To get second term, multiply the first term by 3

So common ratio = 3

Explicit rule for geometric sequence is

$a_n=a_1(r)^{n-1}$

Where a1 is the first term

r is the common ratio

a1= 49 and r= 3

$a_n=49(3)^{n-1}$

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Step-by-step explanation:

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