It is currently 24 Jun 2017, 10:36

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 m and n are integers, then what is the value of (-1)^m

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

1 KUDOS received
Intern
Intern
avatar
Joined: 19 Sep 2010
Posts: 14
If m and n are integers, then what is the value of ( 1)^m + [#permalink]

Show Tags

New post 01 Mar 2011, 01:00
1
This post received
KUDOS
2
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  75% (hard)

Question Stats:

48% (02:27) correct 52% (00:54) wrong based on 121 sessions

HideShow timer Statistics

If m and n are integers, then what is the value of (–1)^m + (–1)^n + (–1)^m · (–1)^n ?
(1) m = 23522101
(2) n = 63522251
[Reveal] Spoiler: OA
Director
Director
avatar
Joined: 13 Nov 2003
Posts: 789
Location: BULGARIA
Re: don't know how to crack [#permalink]

Show Tags

New post 01 Mar 2011, 01:18
Hi,
If you try to group the terms then you will see the solution.
[(-1)^m]*[(-1)^n+(1)]+[(-1)^n]

From A we know that m is odd so the sign will be neg. So no matter what the sign of n is the ans is -1.
from b we know that n is odd which means that the sign is neg. The term in the [] is 0, and the ans is -1.

Hope it helps
1 KUDOS received
Manager
Manager
avatar
Joined: 14 Feb 2011
Posts: 194
Re: don't know how to crack [#permalink]

Show Tags

New post 01 Mar 2011, 02:03
1
This post received
KUDOS
1
This post was
BOOKMARKED
The given expression is \((-1)^m+(-1)^n+(-1)^m.(-1)^n\)

From statement 1, m is odd so \((-1)^m\) = -1

Substituting this value in equation gives us \(-1 +(-1)^n - (-1)^n\) = -1

So, sufficient

From statement 2, n is odd so \((-1)^n\) = -1

Substituting this value in equation gives us \(-1 +(-1)^m - (-1)^m\) = -1

So, sufficient

Hence , answer D
1 KUDOS received
Senior Manager
Senior Manager
avatar
Joined: 10 Jul 2013
Posts: 334
If m and n are integers, then what is the value of (-1)^m [#permalink]

Show Tags

New post 01 Aug 2013, 09:20
1
This post received
KUDOS
If m and n are integers, then what is the value of (-1)^m + (-1)^n + (-1)^m * (-1)^n ?

(1) m = 23522101
(2) n = 63522251

Chapter name: exponents and roots, page: 280, problem set k, number : 5

my solution:
[Reveal] Spoiler:
clearly we can see that m and n both are odd numbers, no matter how long they are , they are just odd numbers.
And there is no chance of m or n to be even because they are given pronouncedly……. So the answer must be (C), because together the statements are sufficient to answer the question.

But the book says, the answer is (B) . the author imagined the m and n sometimes odd and sometimes even to evaluate the answer…….!!!

Have you seen this ?

_________________

Asif vai.....


Last edited by Bunuel on 15 May 2014, 04:10, edited 4 times in total.
Topic Renamed.Edited OA
2 KUDOS received
Verbal Forum Moderator
Verbal Forum Moderator
User avatar
Joined: 10 Oct 2012
Posts: 629
Premium Member
Re: If m and n are integers, then what is the value of (-1)^m [#permalink]

Show Tags

New post 01 Aug 2013, 11:23
2
This post received
KUDOS
Asifpirlo wrote:
Chapter name: exponents and roots, page: 280, problem set k, number : 5

If m and n are integers, then what is the value of (-1)^m + (-1)^n + (-1)^m . (-1)^n ?
(1) m = 23522101
(2) n = 63522251

my solution:
clearly we can see that m and n both are odd numbers, no matter how long they are , they are just odd numbers.
And there is no chance of m or n to be even because they are given pronouncedly……. So the answer must be (C), because together the statements are sufficient to answer the question.

But the book says, the answer is (B) . the author imagined the m and n sometimes odd and sometimes even to evaluate the answer…….!!!

Have you seen this ?


The answer will neither be C nor B. It is D

From F.S 1, we know that m = odd and \((-1)^{odd} = -1\).
Thus, \((-1)^m + (-1)^n + (-1)^m . (-1)^n = -1+(-1)^n-1*(-1)^n = -1\). We get a unique distinct numerical value, Sufficient.

Similarly,from F.S 2, we know that n = odd and thus,
\((-1)^m + (-1)^n + (-1)^m . (-1)^n = -1+(-1)^m-1*(-1)^m = -1\). We get a unique distinct numerical value, Sufficient.

D.
_________________

All that is equal and not-Deep Dive In-equality

Hit and Trial for Integral Solutions

Senior Manager
Senior Manager
avatar
Joined: 10 Jul 2013
Posts: 334
Re: If m and n are integers, then what is the value of (-1)^m [#permalink]

Show Tags

New post 01 Aug 2013, 15:16
mau5 wrote:
Asifpirlo wrote:
Chapter name: exponents and roots, page: 280, problem set k, number : 5

If m and n are integers, then what is the value of (-1)^m + (-1)^n + (-1)^m . (-1)^n ?
(1) m = 23522101
(2) n = 63522251

my solution:
clearly we can see that m and n both are odd numbers, no matter how long they are , they are just odd numbers.
And there is no chance of m or n to be even because they are given pronouncedly……. So the answer must be (C), because together the statements are sufficient to answer the question.

But the book says, the answer is (B) . the author imagined the m and n sometimes odd and sometimes even to evaluate the answer…….!!!

Have you seen this ?


The answer will neither be C nor B. It is D

From F.S 1, we know that m = odd and \((-1)^{odd} = -1\).
Thus, \((-1)^m + (-1)^n + (-1)^m . (-1)^n = -1+(-1)^n-1*(-1)^n = -1\). We get a unique distinct numerical value, Sufficient.

Similarly,from F.S 2, we know that n = odd and thus,
\((-1)^m + (-1)^n + (-1)^m . (-1)^n = -1+(-1)^m-1*(-1)^m = -1\). We get a unique distinct numerical value, Sufficient.

D.


good job man...yes it is an obvious (D)...thanks for sorting out........
_________________

Asif vai.....

Manager
Manager
avatar
Joined: 22 Aug 2013
Posts: 110
Schools: ISB '15
Re: If m and n are integers, then what is the value of (-1)^m [#permalink]

Show Tags

New post 15 May 2014, 03:38
Sorry, dint understand.
How did you get -1 in both the cases.
_________________

Veritas Prep - 650
MGMAT 1 590
MGMAT 2 640 (V48/Q31)

Please help the community by giving Kudos.

Director
Director
User avatar
Joined: 25 Apr 2012
Posts: 727
Location: India
GPA: 3.21
WE: Business Development (Other)
Premium Member Reviews Badge
Re: If m and n are integers, then what is the value of (-1)^m [#permalink]

Show Tags

New post 15 May 2014, 04:01
1
This post was
BOOKMARKED
seabhi wrote:
Sorry, dint understand.
How did you get -1 in both the cases.



If m and n are integers, then what is the value of (-1)^m + (-1)^n + (-1)^m . (-1)^n ?
(1) m = 23522101
(2) n = 63522251

Note that (-1)^ Odd power =-1 and (-1)^Even power =1 and (-1)^0 = 1

St 1 says m is odd so we have the expression as -1 +(-1)^n + (-1)*(-1)^n---------> Thus we get\(-1+(-1)^n - (-1)^n\) or -1

So St1 is sufficient

St 2 says n is odd so we have \((-1)^m + -1 *(-1)^m or -1\)
That's why Ans is D

Hope it helps
_________________


“If you can't fly then run, if you can't run then walk, if you can't walk then crawl, but whatever you do you have to keep moving forward.”

GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 09 Sep 2013
Posts: 15948
Premium Member
Re: If m and n are integers, then what is the value of ( 1)^m + [#permalink]

Show Tags

New post 09 Sep 2016, 05:39
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

Re: If m and n are integers, then what is the value of ( 1)^m +   [#permalink] 09 Sep 2016, 05:39
    Similar topics Author Replies Last post
Similar
Topics:
1 Experts publish their posts in the topic If mn≠0, what is the value of m+1/m-n+1/n? MathRevolution 3 02 Mar 2017, 05:21
4 Experts publish their posts in the topic If m and n are positive integers, what is the value of m+n? 1) m/n=3/5 MathRevolution 3 17 Feb 2017, 23:13
1 Experts publish their posts in the topic m and n are positive integers. What is the value of m? Bunuel 2 16 Mar 2016, 06:47
Experts publish their posts in the topic If m and n are negative integers, what is the value of mn? dreambeliever 6 23 Feb 2016, 02:07
Experts publish their posts in the topic What is the value of {M - N} / {M^2 - N^2}? 1. {M^2 - N^2} = kylexy 14 06 Jan 2011, 09:39
Display posts from previous: Sort by

If m and n are integers, then what is the value of (-1)^m

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


cron

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

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®.