Is |x| < 1 ?

[Obi]

Is |x| < 1 ?

(1) |x + 1| = 2|x - 1|

(2) |x - 3| > 0

Can somebody explain why A is not sufficient in a logical fashion.

[Guest]

|x + 1| = 2|x - 1|

(x+1)=2(x-1)

or

(x+1)=-2(x-1)

then x=3 or x=1/3

so (2) is insufficient

[RonPurewal]

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