00:01
So here we have a monopoly.
00:02
We have a fixed cost of a thousand.
00:05
We have a variable cost, total variable cost of q squared.
00:10
I believe that's q squared.
00:12
And we have a demand curve.
00:13
Quantity demand that is 60 minus 0 .5p.
00:17
The firm expects the contingency.
00:20
So first of all, the inverse is to rewrite in terms of p, right? rewrite for p.
00:26
That's what we mean by inverse.
00:28
So i could rearrange this, is 0 .5p is 60 minus q or p is equal to 120 minus 2 q.
00:37
That would be my inverse demand for a curve.
00:40
B, i want to think first about revenue.
00:43
Revenue is price times quantity.
00:45
I can now sub in that inverse demand curve for p.
00:50
And now i can get marginal revenue, which is the derivative of revenue with respect to quantity, which is 120 minus 4q.
00:57
That would be the marginal demand curve.
01:02
C, marginal cost is the derivative of total cost with respect to quantity, and that's just equal to 2q, right? total cost is now q squared plus 1 ,000, right? it's the two costs added together, but when you differentiate 1 ,000, it just goes.
01:20
So that would be the marginal cost.
01:22
So for d, we want to think about putting marginal revenue equal.
01:27
To marginal cost.
01:29
That defines the firm's maximum profit, right? so if we do that, i get 120 minus 4q is equal to 2q, 120 is equal to 6q, q is equal to 20, and q is equal to 20 will result in a price of 120 minus 2 times 20, which is equal to a price of 80, right? that would be the firm's maximum the profit maximizing choice.
02:01
The revenue is equal to price times quantity, which is going to be 20 times 80, which is equal to 1 ,600.
02:09
And that would be the revenue at the optimal outcome.
02:13
Deadweight loss, i want to visualize.
02:15
So if we think of dead weight loss, right, for e, dead weight loss is demand.
02:22
We have marginal revenue.
02:24
We have marginal cost...