Comparing Radicals

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If x and y are positive integers, is ?

(1)

(2)

Review: Comparing Radicals




Explanation

On the GMAT, the radical sign denotes the positive square root of something (even though, when we solve for a variable squared, there are positive and negative possibilities), so both sides of this inequality are positive. We can therefore square it and obtain:







This is the question we are being asked. On to the statements, separately first.

Statement (1) tells us exactly what we want to know. It says that is a fact, so the answer to the question of whether will be definitively "yes." Sufficient.

Statement (2) looks similar. It simplifies to . We'll analyze by cases. Say . In that case, the statement demands that . So the statement would allow, among other possibilities, and . These two x-y possibilities yield opposite answers to the question posed, so this statement is insufficient.

The correct answer is (A).


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