DS help
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Source: Beat The GMAT — Data Sufficiency |
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gmat25
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Well i tried the cases, for Op A, if p = r, then i replaced r with p in the given question. first of all if u notice sign play no role here as both sides will gonna have same sign. That means the only cases u need to check arevineeshp wrote:Can you post your method and solution that helps you with A? Maybe then we can see if it works.
case 1:-- r = p > 1
case 2:-- 0 < r = p < 1
In both these cases i find the eq'n holds true hence Op A
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Frankenstein
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Hi,gmat25 wrote:Well i tried the cases, for Op A, if p = r, then i replaced r with p in the given question. first of all if u notice sign play no role here as both sides will gonna have same sign. That means the only cases u need to check arevineeshp wrote:Can you post your method and solution that helps you with A? Maybe then we can see if it works.
case 1:-- r = p > 1
case 2:-- 0 < r = p < 1
In both these cases i find the eq'n holds true hence Op A
Why didn't you consider the case r<0? For r<0, the sign of inequality changes because 1/r - 1/(r^2+2) = 2/r(r^2+2). It's sign depends on the sign of r.
If you have considered only r>0, that means you are in fact considering statement(2) as well. Hence, the answer should be C.
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
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gmat25
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I took r < 0 as case earlier but unfortunately made a silly mistake...thanksFrankenstein wrote:Hi,gmat25 wrote:Well i tried the cases, for Op A, if p = r, then i replaced r with p in the given question. first of all if u notice sign play no role here as both sides will gonna have same sign. That means the only cases u need to check arevineeshp wrote:Can you post your method and solution that helps you with A? Maybe then we can see if it works.
case 1:-- r = p > 1
case 2:-- 0 < r = p < 1
In both these cases i find the eq'n holds true hence Op A
Why didn't you consider the case r<0? For r<0, the sign of inequality changes because 1/r - 1/(r^2+2) = 2/r(r^2+2). It's sign depends on the sign of r.
If you have considered only r>0, that means you are in fact considering statement(2) as well. Hence, the answer should be C.
