sequence

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sequence

by ST » Sun Aug 09, 2009 4:55 pm
could someone please explain this?
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by prindaroy » Sun Aug 09, 2009 6:10 pm
Okay so this is a simple word problem;

we just look at consecutive pairs that have a negative product;

for 1,-3,2,5,-4,-6

we get product of pair 1 = 1*-3 = -3 (1 variation)

pair 2 = -3 * 2 = -6 (2 variations so far)

pair 3 = 2*5 = 10 (not a variation)

pair 4 = 5*-4 = -20 (3 variations so far)

pair 5 = -4*-6 = 25 (not a variation)

so the answer is 3 variations

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by ST » Mon Aug 10, 2009 4:13 am
not quite following you but Thank you