Bunuel
If \(s - \frac{1}{s} < \frac{1}{t} - t\), is \(s > t\) ?
(1) \(s > 1\)
(2) \(t > 0\)
The inequality can be transformed as
\(\frac{s^2 - 1}{s}\) < \(\frac{1-t^2}{t}\)
Questions > t
Inference: Does 's' lie to the right of 't' when plotted on a number lineStatement 1\(s > 1\)
As s > 1, the RHS of the inequality is +ve as \(\frac{+ve }{ +ve}\) will yield a +ve result.
We know that the LHS > RHS, so the LHS also has to be positive.
Let's find out for what values of 't' is the LHS positive
\(\frac{1-t^2}{t}\) > 0
\(\frac{(1+t)(1-t)}{t}\) > 0
\(\frac{(t+1)(t-1)}{t}\) < 0
Plotting this over a number line
--------- -1 ---------
0 --------- 1 ---------
The highlighted part denotes the possible values of 't'
As both the ranges are less than 1, we have a definite answer to the question is s > t --
Yes !!Statement 1 is sufficient and we can eliminate B, C and E.
Statement 2\(t > 0\)
We already know from Statement 1, that when \(0 < t < 1\) and \(s > 1\) we have one possible answer to the question - Is \(s > t\) - Yes !.
So let's see if there is any other possibility.
Say t =1, the LHS = 0. Now for s negative values of s, the base equation still holds true and we now have \(s < t\). Is \(s > t\) - No !.
As we have two possible answers this statement is not sufficient.
Option A