Last visit was: 26 Apr 2026, 07:19 It is currently 26 Apr 2026, 07:19
Close
GMAT Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Close
Request Expert Reply
Confirm Cancel
User avatar
Carcass
User avatar
Board of Directors
Joined: 01 Sep 2010
Last visit: 26 Apr 2026
Posts: 4,708
Own Kudos:
37,858
 [33]
Given Kudos: 4,925
Posts: 4,708
Kudos: 37,858
 [33]
1
Kudos
Add Kudos
32
Bookmarks
Bookmark this Post
Most Helpful Reply
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 26 Apr 2026
Posts: 109,837
Own Kudos:
Given Kudos: 105,895
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 109,837
Kudos: 811,375
 [14]
4
Kudos
Add Kudos
10
Bookmarks
Bookmark this Post
User avatar
EvaJager
Joined: 22 Mar 2011
Last visit: 31 Aug 2016
Posts: 513
Own Kudos:
2,371
 [6]
Given Kudos: 43
WE:Science (Education)
Posts: 513
Kudos: 2,371
 [6]
4
Kudos
Add Kudos
2
Bookmarks
Bookmark this Post
General Discussion
User avatar
methevoid
Joined: 02 Jun 2009
Last visit: 12 Aug 2013
Posts: 79
Own Kudos:
Given Kudos: 48
Status:Fighting again to Kill the GMAT devil
Location: New Delhi
Concentration: MBA - Strategy, Operations & General Management
WE 1: Oil and Gas - Engineering & Construction
Posts: 79
Kudos: 168
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Perfect Explanation, Evajager, @Carcass this is a very common mistake which I am also prone to make.
Thanks @Evajager - Your explanation for {B}
Quote:
(2) Since , it follows that , because . cannot be negative!!!
Then, the given inequality becomes , or (we can multiply both sides by , which is positive) and we are again in the situation from (1) above.
Sufficient.

I remember skipping a Question just like this in one of my exams because I gt stuck!!! in solving - | x | < 1/x

Thanks guys you rock!!!
User avatar
EvaJager
Joined: 22 Mar 2011
Last visit: 31 Aug 2016
Posts: 513
Own Kudos:
Given Kudos: 43
WE:Science (Education)
Posts: 513
Kudos: 2,371
Kudos
Add Kudos
Bookmarks
Bookmark this Post
EvaJager
carcass
If x is not equal to zero, is \(| x | < 1\) ??

1) \(x^2\) \(< 1\)

2) \(| x |\) < \(\frac{1}{x}\)

I would like to know if I do in the right manner

question: x id non zero, is \(| x | < 1\) ??? now to be < 1 x must be negative, so the question become " is x negative ???

1) for a square to be < 1 the must be for example \(\frac{- 1}{2}\) ----> x is negative . suff

2) for x to be minor of a certain number that is the reciprocal i.e. : \(-2 < - 1/2\) --------> x is negative. suff

is correct or I should rethink the entire part regarding inequalities ?? because this statement should not take you more that 50 seconds to solve. otherwise you get in trouble with this exam.

Thanks


The condition \(x\) non-zero was given just because statement (2) has \(x\) in the denominator.

x id non zero, is \(| x | < 1\) ???
Not necessarily. \(x\) can be greater than \(1\) or less than \(-1\), in which case, definitely \(|x|\) is not less than \(1.\)

now to be < 1 x must be negative, so the question become " is x negative ??? NO
\(x\) can be between \(0\) and \(1\).

(1) \(x^2\) \(< 1\), take square root from both sides and obtain \(|x|<1\), because \(\sqrt{x^2}=|x|\).
Sufficient.

(2) Since \(|x|<\frac{1}{x}\), it follows that \(x>0\), because \(|x|>0\). \(x\) cannot be negative!!!
Then, the given inequality becomes \(x<\frac{1}{x}\), or \(x^2<1\) (we can multiply both sides by \(x\), which is positive) and we are again in the situation from (1) above.
Sufficient.

Answer D.


Correction: in (2) and we are again in the situation from (1) above. - not exactly, but similar as we have \(x^2<1\) but in addition \(x>0.\) In (1) \(x\) could also be negative.
The conclusion is still correct, as now \(|x|=x<1.\)
User avatar
KarishmaB
Joined: 16 Oct 2010
Last visit: 23 Apr 2026
Posts: 16,441
Own Kudos:
79,415
 [4]
Given Kudos: 485
Location: Pune, India
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 16,441
Kudos: 79,415
 [4]
4
Kudos
Add Kudos
Bookmarks
Bookmark this Post
carcass
If x is not equal to zero, is \(| x | < 1\) ??

1) \(x^2\) \(< 1\)

2) \(| x |\) < \(\frac{1}{x}\)

I would like to know if I do in the right manner

question: x id non zero, is \(| x | < 1\) ??? now to be < 1 x must be negative, so the question become " is x negative ???

1) for a square to be < 1 the must be for example \(\frac{- 1}{2}\) ----> x is negative . suff

2) for x to be minor of a certain number that is the reciprocal i.e. : \(-2 < - 1/2\) --------> x is negative. suff

is correct or I should rethink the entire part regarding inequalities ?? because this statement should not take you more that 50 seconds to solve. otherwise you get in trouble with this exam.

Thanks

I would suggest you to keep 4 ranges in mind when dealing with squares, reciprocals etc.

............... -1........ 0 ........ 1 ..............

Less than -1, -1 to 0, 0 to 1 and greater than 1

You can do the question logically or by plugging in numbers.

Ques: If x is not equal to zero, is \(| x | < 1\) ??
Logically, | x | implies distance from 0 on the number line. So the question becomes "Is x a distance of less than 1 away from 0?" i.e. "Is -1 < x < 1?" given x is not 0.

Statement 1: \(x^2\) \(< 1\)
Square of a number will be less than 1 only if the absolute value of the number is less than 1. This means \(| x | < 1\). The number needn't be negative. If it is positive, it should be less than 1. If it negative, it should be greater than -1.
Or, do you remember how to solve inequalities using the wave? \(x^2 < 1\) is \(x^2 - 1 < 0\) which is \((x - 1)(x + 1) < 0\). This implies -1 < x < 1 but x is not 0.
Or plug in numbers from the given 4 ranges. YOu will see that x must lie in -1 < x < 1.
Sufficient.

Statement 2: \(| x | < \frac{1}{x}\)
First of all, x cannot be negative since | x | is never negative. Since | x | is less than 1/x, 1/x must be positive. Also, x cannot be greater than 1 since then, | x | will be greater than 1/x.
Or plug in numbers from the given 4 ranges. You will see that x must lie in 0 < x < 1.
Sufficient.

Answer (D)
User avatar
Carcass
User avatar
Board of Directors
Joined: 01 Sep 2010
Last visit: 26 Apr 2026
Posts: 4,708
Own Kudos:
Given Kudos: 4,925
Posts: 4,708
Kudos: 37,858
Kudos
Add Kudos
Bookmarks
Bookmark this Post
VeritasPrepKarishma
carcass
If x is not equal to zero, is \(| x | < 1\) ??

1) \(x^2\) \(< 1\)

2) \(| x |\) < \(\frac{1}{x}\)

I would like to know if I do in the right manner

question: x id non zero, is \(| x | < 1\) ??? now to be < 1 x must be negative, so the question become " is x negative ???

1) for a square to be < 1 the must be for example \(\frac{- 1}{2}\) ----> x is negative . suff

2) for x to be minor of a certain number that is the reciprocal i.e. : \(-2 < - 1/2\) --------> x is negative. suff

is correct or I should rethink the entire part regarding inequalities ?? because this statement should not take you more that 50 seconds to solve. otherwise you get in trouble with this exam.

Thanks

I would suggest you to keep 4 ranges in mind when dealing with squares, reciprocals etc.

............... -1........ 0 ........ 1 ..............

Less than -1, -1 to 0, 0 to 1 and greater than 1

You can do the question logically or by plugging in numbers.

Ques: If x is not equal to zero, is \(| x | < 1\) ??
Logically, | x | implies distance from 0 on the number line. So the question becomes "Is x a distance of less than 1 away from 0?" i.e. "Is -1 < x < 1?" given x is not 0.

Statement 1: \(x^2\) \(< 1\)
Square of a number will be less than 1 only if the absolute value of the number is less than 1. This means \(| x | < 1\). The number needn't be negative. If it is positive, it should be less than 1. If it negative, it should be greater than -1.
Or, do you remember how to solve inequalities using the wave? \(x^2 < 1\) is \(x^2 - 1 < 0\) which is \((x - 1)(x + 1) < 0\). This implies -1 < x < 1 but x is not 0.
Or plug in numbers from the given 4 ranges. YOu will see that x must lie in -1 < x < 1.
Sufficient.

Statement 2: \(| x | < \frac{1}{x}\)
First of all, x cannot be negative since | x | is never negative. Since | x | is less than 1/x, 1/x must be positive. Also, x cannot be greater than 1 since then, | x | will be greater than 1/x.
Or plug in numbers from the given 4 ranges. You will see that x must lie in 0 < x < 1.
Sufficient.

Answer (D)

This is the same reasoning that I followed in the first instance with some errors but the path was correct. Specifically the stimulus evaluation : \(| x | < 1\) ------ in this scenario the first one is \(x < 1\) AND \(-x < 1\) so \(x > -1\) ------> \(- 1 < x < 1\)

Thanks Mod :)
avatar
Ndkms
Joined: 09 Aug 2016
Last visit: 26 Jul 2017
Posts: 42
Own Kudos:
Given Kudos: 8
Posts: 42
Kudos: 71
Kudos
Add Kudos
Bookmarks
Bookmark this Post
The general rule of thumb with DS + ineq questions is if you can avoid plug numbers DO IT!

If x is not equal to zero, is |x| < 1 ?

Unraveling the question we have case1 where x < 1 OR case 2 where x > -1

REMEMBER that with ineq. DS questions A suffiecient asnswer is the answer that verifies case1 OR case2 OR BOTH

(1) x^2 < 1
"ROOTING" both sides (i.e. raised both sides in 1/2 power) we have sqrt(x^2) = sqrt(1) = 1 hence |x| < 1 which is SUFFICIENT as verifies case1 and case2 (effectivly if you solve it you get exactly the 2 cases from the question stem). Is important to know that "ROOTING" is allowed here because BOTH sides of the enequality are NOT NEGATIVE.


(2) |x| < 1/x
Solving the ineq. above gives two cases:

caseA: x < 1 / x and caseB x > - 1/x

CaseA: Since x>0 we can multiply both sides and get x^2 < 1. Rooting both sides again (as shown in (1) above) you get |x| < 1 this verifies again case1 and case2 from the question stem. At this point YOU DONT need to go and check caseB.

D is the correct answer
User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 38,988
Own Kudos:
Posts: 38,988
Kudos: 1,118
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Automated notice from GMAT Club BumpBot:

A member just gave Kudos to this thread, showing it’s still useful. I’ve bumped it to the top so more people can benefit. Feel free to add your own questions or solutions.

This post was generated automatically.
Moderators:
Math Expert
109837 posts
498 posts
212 posts