-2 or 2 is the answer. The absolute value of 2 is 2 and the absolute value of -2 is 2 because absolute value can not be negative.
At x = -4 and -8
Take the derivative of the given equation to find rate of change of the graph.
f'(x) = 6x^2 + 72x + 192
At a horizontal tangent, f'(x) = 0, so set the equation equal to 0 and solve. Eventually you get x = -4 and -8
Factor out the common terms in the first two terms, then in the last two terms;
3x^2(b - 3x) - (b - 3x)
Factor out the common term b - 3x
<u>= (b - 3x)(3x^2 - 1)</u>
50 × 500 = 25,000
The answer is 500 runs.