Thursday, September 09, 2010

If x is not equal to zero, is 1/x > 1 ?

1) y/ x > y
2) x^3 > x^2



From statement (1): y/x > y
=> y > xy
=> y(1-x) > 0
y>0 when x is less than 1 or y less than 0> when x is greater than 1 ---- hence insufficient

From statement (2): x^3 > x^2
=> x^2(x-1) > 0
=> x^2 >0 and x>1
Since x>1, 1/x can not be greater than 1 ---- hence sufficient

Hence B

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