x^2 = y ?

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by adthedaddy » Thu Aug 09, 2012 9:12 pm
Opt:1
Squaring both sides, we get
y=x^2
SUFFICIENT

Opt:2
x<y
You cannot get a relation for x^2=y from this
INSUFFICIENT

Thus, [spoiler]ans = A[/spoiler]

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by Ankur87 » Wed Aug 22, 2012 4:07 am
Does x^2 = y ?
(1) square root of y = -x
(2) x < y

SOLUTION :

From 1) square root of y is -x : take any example like sq. rt. of 4 is +_2 and if we ignore +2 and take sq.rt. of 4 as -2. So, if we do -2^2 (which is same as x^2) we will get 4 (same as y).
SUFFICIENT

From 2) INSUFFICIENT. we know x is -ve but it does not provide any other detail.

Ans : A