It is currently 19 Mar 2018, 11:32

### 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

# square root X = 25, then x^3 x^ 2 = A. 5^ 12 B. 5^ 20 C.

Author Message
Senior Manager
Joined: 02 Dec 2007
Posts: 432
square root X = 25, then x^3 x^ 2 = A. 5^ 12 B. 5^ 20 C. [#permalink]

### Show Tags

19 Sep 2008, 10:38
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

square root X = 25, then x^3 – x^ 2 =

A. 5^ 12
B. 5^ 20
C. 6(5^5)
D. 5^4(5^2 + 1)
E. 5^8(5^4 − 1)
Director
Joined: 12 Jul 2008
Posts: 513
Schools: Wharton

### Show Tags

19 Sep 2008, 10:42
1
KUDOS
Nihit wrote:
square root X = 25, then x^3 – x^ 2 =

A. 5^ 12
B. 5^ 20
C. 6(5^5)
D. 5^4(5^2 + 1)
E. 5^8(5^4 − 1)

E

x = 25^2

x^3 – x^ 2 = (25^2)^3 - (25^2)^2
= [(25^2)^2]*(25^2 - 1)
= [((5^2)^2)^2]*[(5^2)^2 - 1]
= [(5^4)^2]*(5^4-1)
= (5^8)*(5^4 - 1)
SVP
Joined: 28 Dec 2005
Posts: 1500

### Show Tags

19 Sep 2008, 14:04
yep, E as well, same method as above
Retired Moderator
Joined: 05 Jul 2006
Posts: 1741

### Show Tags

19 Sep 2008, 16:02
Nihit wrote:
square root X = 25, then x^3 – x^ 2 =

A. 5^ 12
B. 5^ 20
C. 6(5^5)
D. 5^4(5^2 + 1)
E. 5^8(5^4 − 1)

x = 5^4 , x^3 – x^ 2 = x^2(x-1) = (5^4)^2 * (5^4 - 1) = 5^8(5^4 - 1) ...E
Re: X   [#permalink] 19 Sep 2008, 16:02
Display posts from previous: Sort by

# square root X = 25, then x^3 x^ 2 = A. 5^ 12 B. 5^ 20 C.

Moderator: chetan2u

 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®.