Roots of the equation x^2+b x-c=0(b, c>0) are

We know that, if roots are of same sign \Rightarrow Product of root is + ve if roots are of opposite sign \Rightarrow Product of roots is -ve Here, $x^2+b x-c=0$ (b, $c>0$ ) Product of roots $=\frac{-c}{1}=-\mathrm{ve}\therefore$ Roots are of opposite sign.