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It's possible that x=1, since 1/(1+1) = 1/2, which is less than 1.
In this case, x is positive.
It's possible that x=-2, since 1/(-2+1) = -1, which is less than 1.
In this case, x is negative.
INSUFFICIENT.
Statement 2: x-1 is a perfect square
A perfect square is the square of an integer:
0² = 0
1² = 1
2² = 4
3² = 9
And so on.
In the list above, the least possible option for x-1 is 0:
x-1 = 0
x = 1.
Since the least possible option for x is 1, we know that x must be positive.
SUFFICIENT.
The correct answer is B.
-8-1 = -9 is not the square of an integer and thus is NOT a perfect square.[email protected] wrote:The answer is B but im not clear cox if we test value for x-1 for example if X is -8 then -8-1 is a perfect square but does that prove that X is positive?
Please explain-Thanks
As shown by the list above, the smallest perfect square is 0.
