Typical Inequality Question, plz help!

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Typical Inequality Question, plz help!

Riya
If x/|x| < x , then which of the following are true?
a) x>1
b) x>-1
c) |x|<1
d) |x|^2>1
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Re: Typical Inequality Question, plz help!

xyz123
Is it a)?
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Re: Typical Inequality Question, plz help!

Homer Simpson
In reply to this post by Riya
(a) i think

x = 1, they are equal
-1<x<1, LHS is 1 but LHS>RHS
x<-1, again, LHS is a some positive number while RHS is negative

thus x>1
“Operator! Give me the number for 911!”
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Re: Typical Inequality Question, plz help!

Riya
Yes, logically the answer seems to be (a). But if we square both the sides and cancel the x^2 term on both sides, the answer we obtain is (d)  That's the dilemma!
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Re: Typical Inequality Question, plz help!

xyz123
No then it would be 1< |x|
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Re: Typical Inequality Question, plz help!

Homer Simpson
In reply to this post by Riya
agree that |x|^2 > 1 after the squaring thing but consider x = 1/2, -1/2,1,-1  even. then this inequality wont work, right? so i think x>1 is the stronger condition.
“Operator! Give me the number for 911!”
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Re: Typical Inequality Question, plz help!

Riya
In reply to this post by xyz123
It can't be |x|>1 either. If we put x= -2 , the equation given in the question won't be satisfied :/
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Re: Typical Inequality Question, plz help!

Riya
In reply to this post by Homer Simpson
Ok, thanks :)