Inequalities

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Inequalities

by tanyajoseph » Mon Sep 10, 2007 1:19 pm
Is (1/a-b) < b-a?

1) a<b
2) 1< |a-b|

Answer is A, but how ?

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TT

by TT » Mon Sep 10, 2007 3:06 pm
Is (1/a-b) < b-a?

1) a<b
2) 1< |a-b|


st. 1. If a>b, then the lefthand side is negative, but the right hand side is positive. Sufficient.
st. 2. a-b>0, then a>b. -a+b>0, b>a. So insufficient.