diebeatsthegmat wrote:If \frac{x}{|x|}<x which of the following must be true about x?
(A) x>1
(B) x>-1
(C) |x|<1
(D) |x|=1
(E) |x|^2>1
a is my answer choice. whats yours>?
The notation in the question "\frac{x}{|x|}<x" is used in a mathematical typesetting environment called TeX - it's not something you'll ever see on the GMAT. The question should begin:
If x/|x| < x, which of the following...
Now x/|x| is either equal to 1 (if x is positive) or to -1 (if x is negative). So we can rephrase the inequality:
* if x > 0, then 1 < x
* if x < 0, then -1 < x
So there are two ranges of possible values for x; either x > 1, or -1 < x < 0.
From here you can see that the only answer which *must* be true is B, since if x is in either of the ranges above, x is certainly greater than -1. Most of the other answers (besides D) *could* be true, but are not always true.
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