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audia8 · 2009 July 2nd, 06:24 PM

I go with A:
we want to find if (a-b)/(b+a) < 1

1) b^2 > a^2
a^2-b^2<0=>(a+b)(a-b)<0=>(a+b),(a-b) must be one positive(+), one negative(-), therefore (a-b)/(b+a)<0 =>(a-b)/(b+a)<1 sufficient

2) a-b>1 insufficient

2009 July 2nd, 06:24 PM	#5 (permalink)
audia8 I JUST got here. Join Date: Jun 2009 Posts: 6	I go with A: we want to find if (a-b)/(b+a) < 1 1) b^2 > a^2 a^2-b^2<0=>(a+b)(a-b)<0=>(a+b),(a-b) must be one positive(+), one negative(-), therefore (a-b)/(b+a)<0 =>(a-b)/(b+a)<1 sufficient 2) a-b>1 insufficient