In: Economics
p = 240q - 2q^2-4200
To maximize the price wrt to a particular quantity,
d/dq (p) = 0
or d/dq (240qm - 2qm^2-4200) = 0
or 240 - 4qm = 0
or qm = 60
Maximum price = 240 * 60 - 2*60^2 - 4200 = 3000
Let us consider 2 cases where the quantity is 61 and the quantity is 59
Quantity 61:
p = 240 * 61 - 2 * 61^2 - 4200 = 2998
Quantity = 59
p = 240 * 59 - 2*59^2 - 4200 = 2998
So if we move away 1 quantity on either side from the optimal quantity of 60, then the price reduces.
So if the supply of the material is more than 60 (the optimal quantity), the market starts flooding and as a result, producers need to lower prices to sell the product. So the price goes down. This is the significance of the supply curve for q>qm. The price is highest at a quantity of 60.
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