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

 It is currently 22 May 2013, 12:47

# For which of the following values of x is sqrt(1-sqrt(2-sqrt

Author Message
TAGS:
Manager
Joined: 13 Apr 2006
Posts: 56
Followers: 0

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

For which of the following values of x is sqrt(1-sqrt(2-sqrt [#permalink]  18 Jun 2006, 07:46
For which of the following values of x is sqrt(1-sqrt(2-sqrt x)) not a real number?

a. 1
b. 2
c. 3
d. 4
e. 5

Manager
Joined: 09 May 2006
Posts: 100
Location: Bangalore, India
Followers: 2

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

Re: Roots [#permalink]  18 Jun 2006, 07:56
kuristar wrote:
For which of the following values of x is sqrt(1-sqrt(2-sqrt x)) not a real number?

a. 1
b. 2
c. 3
d. 4
e. 5

E

Sqrt(5) = 2.23

In this case there is a negative number under the Sqrt sign which is not a real number
Senior Manager
Joined: 07 Jul 2005
Posts: 407
Location: Sunnyvale, CA
Followers: 2

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

(E) ..
Sqrt(5) > 2, which makes the expression inside sqrt -ve.
Director
Joined: 10 Oct 2005
Posts: 732
Followers: 3

Kudos [?]: 10 [0], given: 0

Re: Roots [#permalink]  18 Jun 2006, 23:23
shobhitb wrote:
kuristar wrote:
For which of the following values of x is sqrt(1-sqrt(2-sqrt x)) not a real number?

a. 1
b. 2
c. 3
d. 4
e. 5

E

Sqrt(5) = 2.23

In this case there is a negative number under the Sqrt sign which is not a real number

agree
In the which of the kind of question always check D and E answer choices first
_________________

IE IMBA 2010

GMAT Club Legend
Joined: 07 Jul 2004
Posts: 5134
Location: Singapore
Followers: 9

Kudos [?]: 87 [0], given: 0

The fastest way is to see sqrt2 will cancel out 2. So sqrt(5) is going to be greater than 2, and sqrt(negative number) = imaginary number.

Ans E
Manager
Joined: 09 Apr 2006
Posts: 177
Location: Somewhere in Wisconsin!
Followers: 1

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

Agree with E.
_________________

Thanks,
Zooroopa

Director
Joined: 28 Dec 2005
Posts: 764
Followers: 1

Kudos [?]: 6 [0], given: 0

Interestingly for all values of x < 1 , the expression is an imaginary number as well
CEO
Joined: 20 Nov 2005
Posts: 2934
Schools: Completed at SAID BUSINESS SCHOOL, OXFORD - Class of 2008
Followers: 7

Kudos [?]: 37 [0], given: 0

Futuristic wrote:
Interestingly for all values of x < 1 , the expression is an imaginary number as well

Not x <1 but for all values x < 0

yes this is E.
_________________

SAID BUSINESS SCHOOL, OXFORD - MBA CLASS OF 2008

Manager
Joined: 14 Mar 2006
Posts: 217
Followers: 1

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

ha, had to look at the definition of a real number. Its E, can't take a sqrt of a negative #.
Similar topics Replies Last post
Similar
Topics:
For which of the following values of x is the equation 2 30 Oct 2005, 22:04
For which of the following values of x is the equation 2 09 Jun 2007, 16:15
For which of the following values of x is the equation 4 08 Dec 2007, 09:19
which of the following is a value of X for which 2 19 Nov 2008, 19:44
4 For which of the following values of x is 12 24 Aug 2010, 12:41
Display posts from previous: Sort by