Maximizing Profit The weekly demand for the Pulsar 40-in. high-definition television is given by the demand equation
$$p=-0.05 x+600 \qquad(0 \leq x \leq 12,000)$$
where $p$ denotes the wholesale unit price in dollars and $x$ denotes the quantity demanded. The weekly total cost function associated with manufacturing these sets is given by
$$C(x)=0.000002 x^{3}-0.03 x^{2}+400 x+80,000$$
where $C(x)$ denotes the total cost incurred in producing $x$ sets. Find the level of production that will yield a maximum profit for the manufacturer.
Hint: Use the quadratic formula.