Weegy: a.
Factor as:
(x - 3)(x + 1)^3 = 0
zeros are at x = 3 and x = -1
y ' = 4x^3 - 12x - 8
4(x - 2)(x + 1)^2
zeros at x = 2 and x = -1
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b.
y " = 12x^2 - 12
y "(2) = 36 which is positive, [ so x = 2 is a minimum point
y "(-1) = 0, an inflection point
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c.
f(x) decreases from [-8, 2] and increases from [2, +8]
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d.
f(x) is negative for x = [-1, 3] and positive for all other real values ]
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