If x is a positive integer, is y^2 (x^3 - x + 1) : DS Archive
Check GMAT Club Decision Tracker for the Latest School Decision Releases http://gmatclub.com/AppTrack

 It is currently 23 Jan 2017, 13:20

### 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

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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# If x is a positive integer, is y^2 (x^3 - x + 1)

 post reply Question banks Downloads My Bookmarks Reviews Important topics
Author Message
VP
Joined: 30 Jun 2008
Posts: 1043
Followers: 14

Kudos [?]: 570 [0], given: 1

If x is a positive integer, is y^2 (x^3 - x + 1) [#permalink]

### Show Tags

01 Oct 2008, 23:00
00:00

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 20 sessions

### HideShow timer Statistics

This topic is locked. If you want to discuss this question please re-post it in the respective forum.

If $$x$$ is a positive integer, is $$y^2 (x^3 - x + 1) > 75?$$

1. $$y > 1$$
2. $$(x-1)^2=16$$
_________________

"You have to find it. No one else can find it for you." - Bjorn Borg

Manager
Joined: 30 Sep 2008
Posts: 111
Followers: 1

Kudos [?]: 19 [0], given: 0

Re: DS - Inequality [#permalink]

### Show Tags

01 Oct 2008, 23:13
(1). y > 1

y = 2, x = 0 -> not satisfy
y = 10, x = 0 -> satisfy

(1) insufficient

(2) (x-1)^2=16, x positive negative => x = 5

x = 5, y = 0 - > not satify
x = 5, y = 1 -> satisfy

=> (2) insufficient

(1) & (2), x = 5, y > 1

y^2 (x^3 - x + 1 ) > = x^3 - x + 1 > = 121 > 75

sufficient

So the answer is C
VP
Joined: 17 Jun 2008
Posts: 1397
Followers: 8

Kudos [?]: 290 [0], given: 0

Re: DS - Inequality [#permalink]

### Show Tags

02 Oct 2008, 00:37
lylya4 wrote:
(1). y > 1

y = 2, x = 0 -> not satisfy
y = 10, x = 0 -> satisfy

(1) insufficient

(2) (x-1)^2=16, x positive negative => x = 5

x = 5, y = 0 - > not satify
x = 5, y = 1 -> satisfy

=> (2) insufficient

(1) & (2), x = 5, y > 1

y^2 (x^3 - x + 1 ) > = x^3 - x + 1 > = 121 > 75

sufficient

So the answer is C

IMO E
x=-3 or 5 with x=-3 we get the opposite answer hence INSUFFI
_________________

cheers
Its Now Or Never

Intern
Joined: 07 Sep 2008
Posts: 25
Followers: 0

Kudos [?]: 0 [0], given: 0

Re: DS - Inequality [#permalink]

### Show Tags

02 Oct 2008, 01:24
Manager,
What is the correct answer to your problem?

My take is that is E cos
1- doesn't give you a value for x
2- x=5 or x = -3 , doesn't give a value for y

Both together, the statement is correct only if x = 5, but for x=-3, it's not valid. so it's E
Intern
Joined: 07 Sep 2008
Posts: 25
Followers: 0

Kudos [?]: 0 [0], given: 0

Re: DS - Inequality [#permalink]

### Show Tags

02 Oct 2008, 01:26
let me correct myself. i didn't see that is says that x is a positive integer, so it's C
Re: DS - Inequality   [#permalink] 02 Oct 2008, 01:26
Display posts from previous: Sort by

# If x is a positive integer, is y^2 (x^3 - x + 1)

 post reply Question banks Downloads My Bookmarks Reviews Important topics

 Powered by phpBB © phpBB Group and phpBB SEO Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.