Example
In the cookie factory, the production function is
$$ q \left( K, L \right) = K L^2 $$The marginal product of capital is
$$ MP_K = \frac{d q \left( K, L \right)}{d K} = L^2 $$Question
In the cookie factory, the production function is `q \left( K, L \right) = K^{25} L^{39}`.
What is the marginal product of capital?
$$
MP_K = \frac{d q \left( K, L \right)}{dK} = \frac{d K^{25} L^{39}}{dK} = 25 K^{25 - 1} L^{39} = 25 K^{24} L^{39}
$$