SOLUTION: I'm having trouble solving using the recursive formula. Here's the problem: "Find the first five terms of the sequence given the following using the recursive formula- a-sub-

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Question 472769: I'm having trouble solving using the recursive formula. Here's the problem:
"Find the first five terms of the sequence given the following using the recursive formula-
a-sub-1 = 8 and a-sub-n = 10-3a-sub-n minus 1, for n ≥ 2
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
a1 = 8, an = 10-3an-1, for n ≥ 2
Substitute n=2 in an = 10-3an-1

an = 10-3an-1

a2 = 10-3a2-1

a2 = 10-3a1

Substitute 8 for a1

a2 = 10-3(8)

a2 = 10-24

a2 = -14

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Substitute n=3 in an = 10-3an-1

an = 10-3an-1

a3 = 10-3a3-1

a3 = 10-3a2

Substitute -14 for a2

a3 = 10-3(-14)

a3 = 10+42

a3 = 52

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Substitute n=4 in an = 10-3an-1

an = 10-3an-1

a4 = 10-3a4-1

a4 = 10-3a3

Substitute 52 for a3

a4 = 10-3(52)

a4 = 10-156

a4 = -146

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Substitute n=5 in an = 10-3an-1

an = 10-3an-1

a5 = 10-3a5-1

a5 = 10-3a4

Substitute -146 for a4

a5 = 10-3(-146)

a5 = 10+438

a5 = 448

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Edwin