plug in...crak.gmat wrote:If x < 0 , what is the value of (-x.|x|) ^ 1/2.
Ans. Should it be -x or x?
let x =-2
(-x.|x|) ^ 1/2
[-(-2).|-2|)^1/2
4^1/2 = 2 which is -X
hope that helps...
Absolute x
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sudhir3127
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let x =-2
(-x.|x|) ^ 1/2
[-(-2).|-2|)^1/2
4^1/2 = 2 which is -X
hope that helps...
sudhir3127 wrote:plug in...crak.gmat wrote:If x < 0 , what is the value of (-x.|x|) ^ 1/2.
Ans. Should it be -x or x?
let x =-2
(-x.|x|) ^ 1/2
[-(-2).|-2|)^1/2
4^1/2 = 2 which is -X
hope that helps...
Yes it does help and that is the correct answer. But the place where I got confused was where you did the final evaluation of 4^1/2. The result could be either 2 or -2? How did you know to go with 2?
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sudhir3127
- Legendary Member
- Posts: 829
- Joined: Mon Jul 07, 2008 10:09 pm
- Location: INDIA
- Thanked: 84 times
- Followed by:3 members
AFAIK .... there no negative square-roots in GMAT... so its always positive...crak.gmat wrote:sudhir3127 wrote:plug in...crak.gmat wrote:If x < 0 , what is the value of (-x.|x|) ^ 1/2.
Ans. Should it be -x or x?
let x =-2
(-x.|x|) ^ 1/2
[-(-2).|-2|)^1/2
4^1/2 = 2 which is -X
hope that helps...
Yes it does help and that is the correct answer. But the place where I got confused was where you did the final evaluation of 4^1/2. The result could be either 2 or -2? How did you know to go with 2?
hope that helps..
