is |x| < 1?

erukumk wrote:

logitech wrote:

erukumk wrote:is |X| < 1?
1) |X+1|=2|X-1|
2)|X-3|!=0

Question can be paraphrased as:

Is X between -1 and + 1 ?

1) |X+1|=2|X-1|

if we take the square of both side and re-arrange it:

3X^2 - 10X + 3 = 0

X = 1/3 or X = 3

INSUF

2) IX-3|!=0

|X-3|!=0 , 0! = 0

Means that X=3

3 is not between -1 and + 1

Sufficient

Hence, B

for statement 1: can you tell me why did you square on both sides??