IMO:Djayanti wrote:if ab≠0 is (a-b/((a^-1)-(b^-1))^-1> a+b
1. IaI >IbI
2. a<b
Please let me know if this is correct!
Inequality
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Source: Beat The GMAT — Data Sufficiency |
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krishnasty
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Can u pls explain how did u arrive at the conclusion?
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Frankenstein
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Hi,jayanti wrote:if ab≠0 is (a-b/((a^-1)-(b^-1))^-1> a+b
1. IaI >IbI
2. a<b
If the question is [(a-b)/((1/a)-(1/b))]^-1 > a+b, my solution:
((1/a)-(1/b))/(a-b) = -1/ab
So, we need to check Is -1/ab > a+b ?
From(1):
a=-1,b=-1/2 -> -1/ab = -2, a+b = -1.5. So, -1/ab < a+b
a=-1,b= 1/2 -> -1/ab = 2, a+b = -0.5. So, -1/ab > a+b
Not sufficient
From(2):
Use the same set
Not sufficient
Both (1) and (2): Use the same set.
Not sufficient
Hence, E
Cheers!
Things are not what they appear to be... nor are they otherwise
Things are not what they appear to be... nor are they otherwise
