Part A The x intercepts represent when the profit is zero. The maximum value is at the vertex and is where the maximum profit occurs. The function is increasing until it reaches the vertex and is decreasing after the vertex. The profit is increasing until it reaches its peak at the vertex and is decreasing after the vertex until they reach the zero. Profits are negative to the left of the first zero and to the right of the second zero

(-inf to 0) negative profit but increasing (0 to 3) increasing profit 3 maximum profit (3 to 6) decreasing profit but still positive (6 to negative infinity) decreasing negative profit

Part B The approximate rate of change is how much the profit decreases when we go from $3 of the item to $5. The graph is required to calculate this

f(5) - f(3)



5-3

Approximate the values of

f(5) and f(3) from your graph

Part C the domain is constrained by x at =0, we cannot sell pay people to take the item. Business wise, we are constrained at x=6 because we do not want to make a negative profit