3x2 + 4x - 4.

By splitting the middle term


3x3 + 4x - 4 = 0


3x2 + (6x - 2x) - 4 = 0


3x2 + 6x - 2x - 4 = 0


3x(x + 2) - 2(x + 2) = 0


(x + 2)(3x - 2) = 0


⇒ x = - 2, 2/3


Verification:


Sum of the zeroes = - (coefficient of x) ÷ coefficient of x2


α + β = - b/a


- 2 + (2/3) = - (4)/3


= - 4/3 = - 4/3


Product of the zeroes = constant term ÷ coefficient of x2


α β = c/a


Product of the zeroes = (- 2) (2/3) = - 4/3


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