If k is not equal to 0, 1, or -1, is 1/k > 0?
(1)1/(k+1)> 0
(2)1/(k-1)> 0
Unconfirmed OA is D. I went for A. Please explain.
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is 1/k > 0?
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shankar.ashwin
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1/k will be > 0, when k is +ve.
Statement 1:
1/(k+1) > 0
This condition satisfies for all values of k>1.
But, condition also satisfies when k = -1/2. k can be +ve or -ve - Insufficient
Statement 2:
1/(k-1) > 0
k can take any value > 1 to satisfy this condition. (Given k cannot be 1)
Thus k should be +ve and > 1. Sufficient.
Answer should be B IMO. Note : Question does not mention k is an integer.
Statement 1:
1/(k+1) > 0
This condition satisfies for all values of k>1.
But, condition also satisfies when k = -1/2. k can be +ve or -ve - Insufficient
Statement 2:
1/(k-1) > 0
k can take any value > 1 to satisfy this condition. (Given k cannot be 1)
Thus k should be +ve and > 1. Sufficient.
Answer should be B IMO. Note : Question does not mention k is an integer.
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Ian Stewart
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"1/k > 0" means exactly the same thing as "k > 0". Similarly, 1/(k+1) > 0 just means that k + 1 > 0, or that k > -1. So Statement 1 is not sufficient. Since 1/(k-1) > 0 just means that k - 1 > 0, or that k > 1, Statement 2 is sufficient.vzzai wrote:If k is not equal to 0, 1, or -1, is 1/k > 0?
(1)1/(k+1)> 0
(2)1/(k-1)> 0
Unconfirmed OA is D. I went for A. Please explain.
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