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HELP!!!! please :(

Find the first six terms of the sequence.
a1 = -3, an = 2 times an-1

The answer choices are:
A. -6, -12, -24, -48, -96, -192
B. -3, -6, -12, -24, -48, -96
C. 0, 2, -6, -4, -2, 0
D. -3, -6, -4, -2, 0, 2

HELP!!!! please :( Find the first six terms of the sequence. a1 = -3, an = 2 times-example-1
User Puchacz
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2 Answers

2 votes
your sequence starts with -3 and multiplies every time by 2
so
B) -3, -6, -12, -24, -48, -96
is correct
User Gala
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8.0k points
7 votes
This is a geometric sequence because each term is 2 times the previous term, called the common ratio, or "r" and it always has the form:

a(n)=ar^(n-1), a=initial term, r=common ratio, n=term number, and in this case:

a(n)=-3(2^(n-1)) so the first six terms are:

-3,-6,-12,-24,-48,-96
User Boris Zbarsky
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8.2k points

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