Question

If $\sqrt{5}\mathrm{and}-\sqrt{5}$ are two zeroes of the polynomial x³ + 3x² − 5x − 15, then its third zero is

(a) 3
(b) −3
(c) 5
(d) −5

Answer 1

Let andbe the given zeros and be the third zero of the polynomial . Then,

Substitutingandin

We get

Hence, the correct choice is