SOLUTION: What are the next three termsand describe the pattern? -1, 2, -4, 8

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Question 656507: What are the next three termsand describe the pattern?
-1, 2, -4, 8
Found 2 solutions by stanbon, MathLover1:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
What are the next three termsand describe the pattern?
-1, 2, -4, 8
----
1st: -1
2nd: -1*-2 = 2
3rd: 2*-2 = -4
4th: -4*-2 = 8
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Pattern:
a(1) = -1
--
a(n) = -2*a(n-1) for n = 2,3,4....
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Cheers,
Stan H.
============

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

-1, 2, -4, 8,........
is an infinite sequence where every term doubles multiplying with -2
-1%2A-2=2,
2%28-2%29=-4,
-4%28-2%29=8,
8%28-2%29=-16,
-16%28-2%29=32
32%28-2%29=-64.....so, your sequence is
-1, 2, -4, 8,-16,32,-64.....