Okay, so this is Firm 1's best response as a function of q2.

公司1的最佳对策是q2的函数
What is Firm 2's best response as a function of q1?

q1的函数即公司2的最佳对策是什么
Let's just... We'll get there, just to remind you,

我们当然也能算出来提醒一下各位
the way we read this is you give me a quantity of Firm 2,

这个图像的个意思是任意给出公司2产量
I find Firm 1's best response

然后通过这条粉色的线
by going across to the pink line and dropping down.

就可找出与之对应的公司1的最佳对策
So if Firm 2 produces this amount

如果公司2的产量是这么多
then Firm 1's best response is this amount.

那么公司1的最佳对策就是这个产量
If Firm 2 produces this amount

如果公司2的产量是这么多
then Firm 1's best response is this amount.

那么公司1的最佳对策就是这个产量
Now conversely, how do we find Firm 2's best response as a function of q1?

反过来如何由q1求公司2最佳对策的方程
What does that look like?

方程会是什么样的呢