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by Brent@GMATPrepNow » Fri Nov 23, 2012 8:35 am
soni_pallavi wrote: If x is not equal to 0,then sqrt(x^2)/x =

a)-1
b)0
c)1
d)x
e)|x|/x

Ans E
One approach:

Recognize that sqrt(x^2) = |x| for all values of x (a commonly-tested concept on the GMAT)

So, we can replace sqrt(x^2) with |x| to get:
sqrt(x^2)/x = |x|/x = E

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
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GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 16207
Joined: Mon Dec 08, 2008 6:26 pm
Location: Vancouver, BC
Thanked: 5254 times
Followed by:1268 members
GMAT Score:770

by Brent@GMATPrepNow » Fri Nov 23, 2012 8:40 am
soni_pallavi wrote: If x is not equal to 0,then sqrt(x^2)/x =

a)-1
b)0
c)1
d)x
e)|x|/x

Ans E
Second approach:

Plug in some values of x and see what happens.

Try x = 3: sqrt(3^2)/3 = sqrt(9)/3 = 3/3 = 1
When we check the answer choices, we see that the correct answer could be C or E

Try x = -3: sqrt[(-3)^2]/(-3) = sqrt(9)/(-3) = 3/(-3) = -1
When we check the answer choices, we see that the correct answer could be A or E

From these two cases, we can see that the correct answer is E

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
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