00:01
So here, what we have to think about what we know about competition.
00:03
We're first of all told that the cost function for the firm is 25 minus 4q plus q squared.
00:10
Well, in competition, the optimization requires optimization.
00:18
That doesn't seem right.
00:26
Optimization requires, sorry about that.
00:28
Price is equal to marginal cost, right? that's what's going on.
00:33
Firms want to produce up until their marginal cost is equal to the price.
00:39
So i want to find the marginal cost here, right? the marginal cost, which is the derivative of c with respect to q, is equal to minus 4 plus 2q.
00:50
And i want to set this equal to the price.
00:52
So if we have a market, quantity, and price, well, i know that the individual supply curve is going to look something.
01:03
Like this, right? of course, you can't supply a negative price, but that would be the marginal supply curve for one firm.
01:12
Now we have 40 firms...