alex.gellatly wrote:If r and s are the roots of the equation x2+ bx + c = 0,where b and c are constants, is rs < 0 ?
(1) b<0
(2) c < 0
Thanks
For any question in the form ax²+bx+c=0:
The sum of the roots = -b/a.
The product of the roots = c/a.
In the equation above, a=1.
Thus, the product of the roots = c/1 = c.
Question rephrased: Is c<0?
Statement 1: b<0.
No way to determine whether c<0.
INSUFFICIENT.
Statement 2: c<0.
SUFFICIENT.
The correct answer is
B.
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