題組內容

3. (24 %)

Consider a duopoly market that consists of two firms, OpenAI and Google. The competition proceeds as follows:



Each firm has the following cost function:

$$Ci(qi, xi, xj) = (70 - (xi + xj))qi + 2xi^2,$$

where $xj$ is the R&D level the other firm chooses. Let the inverse demand function of the market be $P = 100 - \frac{1}{3}Q$, where $Q = qO + q_G$.

(e) Find the social welfare under this scenario, where the social welfare is defined as the sum of the consumer surplus and the firms' profits.