Find all School-related info fast with the new School-Specific MBA Forum

 It is currently 07 Jul 2015, 21:12

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

The three integers X, Y, and Z. Is their product XYZ = zero

Author Message
TAGS:
SVP
Joined: 05 Jul 2006
Posts: 1516
Followers: 5

Kudos [?]: 127 [0], given: 39

The three integers X, Y, and Z. Is their product XYZ = zero [#permalink]  11 Sep 2006, 09:17
The three integers X, Y, and Z. Is their product XYZ = zero

(1) X^Y=1
(2) X=Y=Z
Director
Joined: 13 Nov 2003
Posts: 790
Location: BULGARIA
Followers: 1

Kudos [?]: 30 [0], given: 0

Another good one
Think it is C)
From A) X=1, Y=1 or X=5,Y=0 then stem may be or may not be 0
B) by itself is not suff-all three may be 0 or any other integer
From both when X=Y=Z=1 we get ans to question
C
SVP
Joined: 01 May 2006
Posts: 1798
Followers: 8

Kudos [?]: 102 [0], given: 0

(E)

Statment 1:
X^Y=1 implies that
> X=1 and Y is any integer
or
> X is any integer and Y=0

Statment 2:
X=Y=Z brings nothing

(1) combined with (2)
X=Y=Z=1 works by giving 1^1=1
or
X=Y=Z=0 works by giving 0^0=1

So, it's insufficient.
Director
Joined: 09 Oct 2005
Posts: 720
Followers: 3

Kudos [?]: 14 [0], given: 0

Re: Exponents [#permalink]  11 Sep 2006, 09:50
yezz wrote:
The three integers X, Y, and Z. Is their product XYZ = zero

(1) X^Y=1
(2) X=Y=Z

A it is
x^y=1
x^y=x^0
y=0 so xyz=0

or x=1!
_________________

IE IMBA 2010

Director
Joined: 13 Nov 2003
Posts: 790
Location: BULGARIA
Followers: 1

Kudos [?]: 30 [0], given: 0

Hallo Fig,
SVP
Joined: 01 May 2006
Posts: 1798
Followers: 8

Kudos [?]: 102 [0], given: 0

I confirm

X^0=1 where X could be any real number
GMAT Instructor
Joined: 04 Jul 2006
Posts: 1266
Followers: 24

Kudos [?]: 167 [0], given: 0

Fig wrote:
I confirm

X^0=1 where X could be any real number

Any real number EXCEPT 0 0^0 is undefined , as is 0/0
VP
Joined: 02 Jun 2006
Posts: 1266
Followers: 2

Kudos [?]: 48 [0], given: 0

Q : Is XYZ = 0?

S1: X^Y = 1

Either X = 1 => X^Y =1 XYZ = YZ
or Y = 0 => XYZ = 0

Not sufficient.

S2: X=Y=Z

Could be anything.. Not sufficient.

S1 & S2:
X^Y = 1, if X = 1, XYZ = 1, Sufficient.
Y=0, XYZ = 0, Sufficient,

Manager
Joined: 01 Jun 2006
Posts: 141
Followers: 1

Kudos [?]: 2 [0], given: 0

E in my opinion if consider 0^0=1
But if consider 0^0=0 so we got x,y,z must be equal 1 and xyz<>0 so C it is.
Plz post OA yezz
Director
Joined: 23 Jun 2005
Posts: 847
GMAT 1: 740 Q48 V42
Followers: 5

Kudos [?]: 36 [0], given: 1

Same dilemma as everyone else. Vote for E
Intern
Joined: 27 Aug 2006
Posts: 18
Followers: 0

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

Got the following from the purpulemath exponent chapter.

http://purplemath.com/modules/exponent2.htm

Another comment: Please don't ask me to "define" 00. There are at least two ways of looking at this quantity:

* Anything to the zero power is "1", so 0^0 = 1.
* Zero to any power is zero, so 0^0 = 0.

As far as I know, the "math gods" have not yet settled on a "definition" of 00. In fact, in calculus, "00" will be called an "indeterminant form". If this quantity comes up on class, don't assume: ask your instructor what you should do with it.

I would go w/ E as it's not clear what's the value of 0^0.
CEO
Joined: 20 Nov 2005
Posts: 2910
Schools: Completed at SAID BUSINESS SCHOOL, OXFORD - Class of 2008
Followers: 19

Kudos [?]: 133 [0], given: 0

frommirage wrote:
If this quantity comes up on class, don't assume: ask your instructor what you should do with it.

Kevincan is a Kaplan instructor(with 780 score) and he has already confirmed that 0^0 is undefined. (See his post above)
_________________

SAID BUSINESS SCHOOL, OXFORD - MBA CLASS OF 2008

SVP
Joined: 01 May 2006
Posts: 1798
Followers: 8

Kudos [?]: 102 [0], given: 0

I maintain my point of view It's a result very specific and famous for it

To the ones that doubt, i suggest that they use the window calculator for example. They can calculate 0^0=1.... The result is 1

And to be sure, they can try:
> -1,2^2,1 >>>> Invalid input function
> 1/0 >>>> cannot divid by zero

In addition, this result is required for a "Serie" representing a fonction. For the ones who remind it, we have
f(x)= Sigma( a(k)*x^k ) where k start from 0 and tend to infinate.

We can imagine imagine a fonction defined for a the value of x=0 thus
f(0) = a(0)*0^0 = a(0)

Last edited by Fig on 12 Sep 2006, 02:10, edited 3 times in total.
VP
Joined: 25 Jun 2006
Posts: 1173
Followers: 2

Kudos [?]: 79 [0], given: 0

C is right. 0^0 is invalid math expression. they can only be 1.
CEO
Joined: 20 Nov 2005
Posts: 2910
Schools: Completed at SAID BUSINESS SCHOOL, OXFORD - Class of 2008
Followers: 19

Kudos [?]: 133 [0], given: 0

Fig wrote:
I maintain my point of view It's a result very specific and famous for it

To the ones that doubt, i suggest that they use the window calculator for example. They can calculate 0^0=1.... The result is 1

And to be sure, they can try:
> -1,2^2,1 >>>> Invalid input function
> 1/0 >>>> cannot divid by zero

In addition, this result is required for a "Serie" representing a fonction. For the ones who remind it, we have
f(x)= Sigma( a(k)*x^k ) where k start from 0 and tend to infinate.

We can imagine imagine a fonction defined for a the value of x=0 thus
f(0) = a(0)*0^0 = a(0)

Don't be confused. Windows calculator is not a maths standard. Windows did not design calculator to clarify the math fundamentals. See the below link. It is clearly stated that "A number other than 0 taken to the power 0 is defined to be 1"
http://mathworld.wolfram.com/Power.html

NOTE: This is one of the trusted link.
_________________

SAID BUSINESS SCHOOL, OXFORD - MBA CLASS OF 2008

SVP
Joined: 01 May 2006
Posts: 1798
Followers: 8

Kudos [?]: 102 [0], given: 0

Interesting link The content does not state on 0^0.

Moreover, concerning calculators, I have tried on 3 differents, one of them is my old HP 48S confirmed it ... Excell works on it too... and so on Windows calculator is just a common and easy-to-access calculator

I personnaly practiced, well a few time ago, some math problems involving 0^0. As i said, a 'serie' represating a fonction is one application.

Some examples:
> f(x) = a0 + a1*x
= Sigma ( a(k)*x^k)
= a(0)*X^0+a(1)*X^1
Thus, F(0) = a(0)*0^0+a(1)*0^1 = a(0)

> f(x) = a0 + a1*x + a2*x^2
= Sigma ( a(k)*x^k)
= (0)*X^0+a(1)*X^1+a(2)*X^2
Thus, F(0) = a(0)*0^0+a(1)*0^1+a(2)*0^2 = a(0)

We can definie sin(), cos() etc... by Sigma ( a(k)*x^k) with k starting at 0

Sorry for it, this is a french link presenting famous series in application for physics:
http://www.sciences.univ-nantes.fr/physique/perso/blanquet/conducti/a1besleg/a1besleg.htm

U can notice that k starts at 0 in
Director
Joined: 09 Oct 2005
Posts: 720
Followers: 3

Kudos [?]: 14 [0], given: 0

great discussion but whats the OA?
_________________

IE IMBA 2010

SVP
Joined: 05 Jul 2006
Posts: 1516
Followers: 5

Kudos [?]: 127 [0], given: 39

THANKS EVERYONE, C is correct OA

(1) X^Y=1 follows that 1^1=1, 0^1=1, and â€“1^0=1: NOT ENOUGH
(2) is of no use

combine , X=Y=Z=1, so the product does not equal to a zero.

thus, C.
SVP
Joined: 01 May 2006
Posts: 1798
Followers: 8

Kudos [?]: 102 [0], given: 0

Could we have the source of it?

PS: Those who want to try online 0^0
http://www.math.com/students/calculators/source/scientific.htm

PS2: A nice function drawer
http://www.coolmath.com/graphit/index.html
CEO
Joined: 20 Nov 2005
Posts: 2910
Schools: Completed at SAID BUSINESS SCHOOL, OXFORD - Class of 2008
Followers: 19

Kudos [?]: 133 [0], given: 0

Fig wrote:
Could we have the source of it?

PS: Those who want to try online 0^0
http://www.math.com/students/calculators/source/scientific.htm

PS2: A nice function drawer
http://www.coolmath.com/graphit/index.html

Fig,

Don't rely on calculators but rely on math theorems.
_________________

SAID BUSINESS SCHOOL, OXFORD - MBA CLASS OF 2008

Go to page    1   2    Next  [ 29 posts ]

Similar topics Replies Last post
Similar
Topics:
1 If x, y, and z are consecutive integers, is x+y+z divisble by 3? 4 22 Feb 2015, 03:49
Clarity on what " x,y,z are consecutive integers" means 3 16 Sep 2011, 10:19
3 If integers x, y and z are greater than 1 what is the value 21 04 Aug 2008, 10:05
x, y and z are three digits numbers, and x=y+z. Is the 2 03 Nov 2007, 16:52
GMATPrep - Mod x,y,z 2 04 May 2007, 12:41
Display posts from previous: Sort by