It is currently 19 Nov 2017, 11:04

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

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

If g is an integer what is the value of (-1)^(g^4-1)

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
Director
Director
avatar
Joined: 01 Aug 2008
Posts: 727

Kudos [?]: 866 [0], given: 99

If g is an integer what is the value of (-1)^(g^4-1) [#permalink]

Show Tags

New post 21 Dec 2008, 09:55
3
This post was
BOOKMARKED
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

If \(g\) is an integer what is the value of \((-1)^{g^4 - 1}\) ?

(1) \(g^2<{1}\)
(2) \(g^2+2 g=0\)

Source: GMAT Club Tests - hardest GMAT questions

Last edited by Bunuel on 13 Dec 2013, 07:08, edited 2 times in total.
Updated.

Kudos [?]: 866 [0], given: 99

Expert Post
3 KUDOS received
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 42257

Kudos [?]: 132700 [3], given: 12335

Re: What is the value of (-1)^{g^4 + g - 1} ? 1. g is an [#permalink]

Show Tags

New post 19 Dec 2012, 06:40
3
This post received
KUDOS
Expert's post
1
This post was
BOOKMARKED
ugimba wrote:
What is the value of \((-1)^{g^4 + g - 1}\) ?

1. \(g\) is an integer
2. \(g\) is even

[Reveal] Spoiler: OA
D

Source: GMAT Club Tests - hardest GMAT questions

shouldn't we consider negative values for option 1? ( 'g' is integer)? in this case, then A wont fit right?


BELOW IS REVISED VERSION OF THIS QUESTION:
If \(g\) is an integer what is the value of \((-1)^{g^4 - 1}\) ?

(1) \(g^2<{1}\)
(2) \(g^2+2 g=0\)

SOLUTION:
(1) \(g^2<{1}\) --> since \(g\) is an integer then \(g=0\). Sufficient to calculate the value of \((-1)^{g^4 - 1}\).

(2) \(g^2+2g=0\) --> \(g(g+2)=0\) --> \(g=0\) or \(g=-2\). Since both possible values of \(g\) are even then \((-1)^{even^4 - 1}=(-1)^{even-1}=(-1)^{odd}=-1\). Sufficient.

Answer: D.
_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Kudos [?]: 132700 [3], given: 12335

VP
VP
avatar
Status: Final Lap Up!!!
Affiliations: NYK Line
Joined: 21 Sep 2012
Posts: 1078

Kudos [?]: 661 [0], given: 70

Location: India
GMAT 1: 410 Q35 V11
GMAT 2: 530 Q44 V20
GMAT 3: 630 Q45 V31
GPA: 3.84
WE: Engineering (Transportation)
Re: What is the value of (-1)^{g^4 + g - 1} ? 1. g is an [#permalink]

Show Tags

New post 19 Dec 2012, 17:14
good question really tricky, i went on select B in hurry

Kudos [?]: 661 [0], given: 70

VP
VP
avatar
Status: Final Lap Up!!!
Affiliations: NYK Line
Joined: 21 Sep 2012
Posts: 1078

Kudos [?]: 661 [0], given: 70

Location: India
GMAT 1: 410 Q35 V11
GMAT 2: 530 Q44 V20
GMAT 3: 630 Q45 V31
GPA: 3.84
WE: Engineering (Transportation)
Re: What is the value of (-1)^{g^4 + g - 1} ? 1. g is an [#permalink]

Show Tags

New post 19 Dec 2012, 17:19
Bunuel wrote:
ugimba wrote:
What is the value of \((-1)^{g^4 + g - 1}\) ?

1. \(g\) is an integer
2. \(g\) is even

[Reveal] Spoiler: OA
D

Source: GMAT Club Tests - hardest GMAT questions

shouldn't we consider negative values for option 1? ( 'g' is integer)? in this case, then A wont fit right?


BELOW IS REVISED VERSION OF THIS QUESTION:
If \(g\) is an integer what is the value of \((-1)^{g^4 - 1}\) ?

(1) \(g^2<{1}\)
(2) \(g^2+2 g=0\)

SOLUTION:
(1) \(g^2<{1}\) --> since \(g\) is an integer then \(g=0\). Sufficient to calculate the value of \((-1)^{g^4 - 1}\).

(2) \(g^2+2g=0\) --> \(g(g+2)=0\) --> \(g=0\) or \(g=-2\). Since both possible values of \(g\) are even then \((-1)^{even^4 - 1}=(-1)^{even-1}=(-1)^{odd}=-1\). Sufficient.

Answer: D.



Superb question, since g^2<1 g cannot have any value except zero had it been g<1 than the answer would have been B

Kudos [?]: 661 [0], given: 70

Re: What is the value of (-1)^{g^4 + g - 1} ? 1. g is an   [#permalink] 19 Dec 2012, 17:19
Display posts from previous: Sort by

If g is an integer what is the value of (-1)^(g^4-1)

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  

Moderator: Bunuel



GMAT Club MBA Forum Home| About| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

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®.