Inequalities and Modulus

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Inequalities and Modulus

by er_priyankajolly » Tue Aug 03, 2010 9:26 am
Is x > y?

(1) x^2 > y

(2) x - |y| > 0

Can you please suggest me ways to handle inequalities. I take a lot of time to solve inequality DS questions.
I usually face problems in choosing numbers to handle such questions

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by Fiver » Tue Aug 03, 2010 10:38 am
Is x>y ?

st1] x^2 > y
Here if x <0 such that |x| > y, then the ans to the question is no.
If 0<y<x then the ans to the question is yes.

Insuff.

St2] x - |y| > 0

this means x > |y|

|y| must be = or > 0
hence x must be > 0, while y could be -ve, 0 or +ve.
In all the 3 cases x must be > y.

Choose B.

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by dinesh19aug » Tue Aug 03, 2010 10:41 pm
Pick values

Stmt1: x =2 and y =1 x>y
x =-2 and y =1 x< y Hence Not Suff. I get two contradictory values

Stmt2: x =2 and y =1 . x>y
x= 2 and y = -1 x>y SUFF


Ans B