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Source: — Problem Solving |

by diebeatsthegmat » Mon Nov 01, 2010 9:55 am
sindhujah_kk wrote:If X is not equal to 0. Then √(x^2)/x = ?

A. -1
B. 0
C. 1
D. x
E. IxI / x

Ans: E

Please correct me If i'm wrong.

I got the answer C.
I took √(x^2)/x = |x|/x = x/x= 1
this question is posted...
ok, if the squroot of a numbers : 9, 4 , it will be 3, 4
i meant V(9)^2=3
but if Vx^2=|x| and |x|= +,- x
so if x>0 so the answer will be 1 , C
if x<0 the answer will be -1 because |x| when x<0 is still x while x in denominator is -x
thus E makes sense
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by Rahul@gurome » Mon Nov 01, 2010 10:27 am
sindhujah_kk wrote:If X is not equal to 0. Then √(x^2)/x = ?

A. -1
B. 0
C. 1
D. x
E. IxI / x

Ans: E

Please correct me If i'm wrong.

I got the answer C.
I took √(x^2)/x = |x|/x = x/x= 1
Your mistake is the red one.
|x| means the absolute value of x, thus
  • (1) |x| = x , if x positive
    (2) |x| = -x , if x negative
Therefore, √(x^2)/x = |x|/x
  • = x/x = 1 , if x positive
    = -x/x = -1 , if x negative
The correct answer is E.
Rahul Lakhani
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