profit maximizing - 經濟

想請問:

Find profit-maximizing levels of inputs for the production function,
where x is the level of production and k and l are levels of inputs.
Let p, r and w be prices for the output and inputs.


x=2√kl


是用 利潤=p*x-w*l-r*k 再偏微分嗎?


謝謝~

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