Q13 of 109 Page 3

If the product of two zeros of the polynomial f (x) = 2xZ3 + 6x2 – 4x + 9 is 3, then its third zero is

Given;


f(x) = 2x3 + 6x2 – 4x + 9


Product of the two zeros = 3


a = 2,


b = 6


c = – 4


d = 9


Let the zeros of f(x) be p, q, r


Product of the zeroes = – d/a


p×q×r = – 9/2


3r = – 9/2 … (given p×q = 3)


r = – 3/2


Hence,


Third zero = – 3/2

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