Given equation is

On dividing by , we get

Taking ' + ' sign, we get

Taking '-' sign, we get

Let be the roots of Eq. (ii) and be the roots of Eq. (iii).
Then,
and
and
and
Clearly, and
∴ Either will be imaginary or both real and positive according to the Eq. (i) has atleast two distinct negative roots. Therefore, both and must be negative.
Therefore,
(i) , which is true as .

(ii)

all a.

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