number properties

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number properties

by sud21 » Fri Jan 13, 2012 5:43 am
If r and s are root of x^2+bx+c=0, rs<0?
1). b<0
2). c<0

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by user123321 » Fri Jan 13, 2012 6:16 am
sud21 wrote:If r and s are root of x^2+bx+c=0, rs<0?
1). b<0
2). c<0
since r,s are roots of the equation and product of roots is c, the question is asking whether c<0 or not?

1) insuff.
2) suff.

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