Q3 of 64 Page 43

Find the zeros, the sum of the zeros and the product of the zeros of the quadratic polynomial p(x) = 3x2 — x — 4

Here p(x) = 3x2 — x — 4


To find the zeros of p(x), let p(x) = 0


∴3x2 — x — 4 = 0


∴ 3x2 + 3x – 4x – 4 = 0


∴ 3x(x + 1) – 4(x + 1) = 0


∴ (3x – 4)(x + 1) = 0


∴ x = or x = –1


⇒ and –1are the zeros of the quadratic polynomial p(x).


Sum of zeros = + (–1) =


Product of zeros = × (–1) = –


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