产出越大，平均成本越低；当平均成本是产出递减函数时，边际成本总是低于平均成本。

When average costs decline in output, marginal cost is always less than average cost.

youdao

产出越大，平均成本越低；当平均成本是产出递减函数时，边际成本总是低于平均成本。

When average costs decline in output, marginal cost is always less than average cost.

youdao