Question

If the sum of the zeros of the quadratic polynomial kx²+2x+3k is equal to the product of its zeros then k = ?

(a) 1/3
(b) −1/3
(c) 2/3
(d) −2/3

Answer 1

-2 + √(4 - 12k) + (-2) - √(4 - 12k) = -4

(-2 + √(4 - 12k))(-2 - √(4 - 12k)) = 4 - (4 - 12k)

= 12k

12k = -4, so k = -1/3.