If a ab? (1) ab

Question

If a < b, is a^2 > ab?

(1) ab < 0
(2) a + b = 0

Bunuel · Accepted Answer

If a < b, is a^2 > ab? (1) ab < 0. This statement tells us that a and b have opposite signs. Now, since we also know that a < b, then a < 0 < b. Thus, (a^2 = positive) > (ab = negative). Sufficient. (2) a + b = 0. This, together with a < b, also implies that a < 0 < b. So, basically the same here. Sufficient. Answer: D. Hope it's clear.

GMATinsight · Answer

Question: Is a^2 > ab? Question: Is a^2 -ab > 0 ? Question REPHRASED: Is a*(a - b) > 0 ? But since we already know that a < b i.e. a-b < 0 So for a*(a - b) > 0 , Given, a-b < 0 , a must be Less than 0 Question REPHRASED: Is a < 0? Statement 1 : ab < 0 for a < b and ab < 0 (i.e. one of a and b is positive and other negative) ie. b must be positive and a must be negative i.e. a < 0 SUFFICIENT Statement 2 : a + b = 0 i.e. b = -a and also, a < b i.e. b must be Positive and a must be Negative SUFFICIENT Answer: Option D

TarunKumar1234 · Answer

If a < b, is a^2 > ab? question can be rephrased as a*(a-b)> 0 or not? Stat1: ab < 0 so, either a = -ve and b = +ve, then, a 0 and, if a = +ve and b = -ve, then a 0 or, we can say, a = +ve and b = -ve, then a

TarunKumar1234 · Answer

GMATinsight if b= 2, then a cannot be 1, as ab = 2 >0, and, it is given, ab <0 so, a = -ve value is possible only. Please review it.

GCMEMBER · Answer

If a < b, is a^2 > ab?

a < b
a-b < 0

Is a^2 > ab
or a(a-b) > 0
or a < 0?

(1) ab < 0
a < b
So, a < 0 and b > 0
Sufficient

(2) a + b = 0
a < b
So, a < 0 and b > 0
Sufficient

Option D

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Archit3110 · Answer

Given a0? a>0 and a>b #1 ab<0 Possible only when a is -ve and b +be Therefore sufficient to say that validation statemt is false sufficient #2 a+b=0 Where again as in #1 a has to be -ve and b of same.number but +ve therefore validation statement is false again Sufficient. Option D is correct

If a < b, is a^2 > ab? (1) ab < 0 (2) a + b = 0

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