MC 边际成本计算器（两点、成本表、成本函数）Marginal Cost Calculator (Two Points, Cost Table, Cost Function)

使用说明与常见问题How-to & FAQ

「边际成本计算器（两点、成本表、成本函数）」是什么？What is the Marginal Cost Calculator (Two Points, Cost Table, Cost Function) tool?

三种算法：由两个产量水平和对应总成本求边际成本 ΔTC/ΔQ；由一组产量和总成本数据逐段列出边际成本和平均成本；或由二次成本函数 TC = a + bQ + cQ² 求指定产量下的边际成本 MC = b + 2cQ、平均成本和平均成本最低点。本地处理。Three ways: marginal cost ΔTC/ΔQ from two output levels and their total costs; a step-by-step table of marginal and average cost from a list of quantities and total costs; or, for a quadratic cost function TC = a + bQ + cQ², the marginal cost MC = b + 2cQ at a chosen output, the average cost and where average cost is lowest. Processed locally.

如何使用「边际成本计算器（两点、成本表、成本函数）」？How do I use the Marginal Cost Calculator (Two Points, Cost Table, Cost Function) tool?

在「边际成本计算器（两点、成本表、成本函数）」中，填写「算法」、「原总成本」、「新总成本」、「原产量」、「新产量」等参数，结果会随输入实时计算并显示在下方。In the Marginal Cost Calculator (Two Points, Cost Table, Cost Function): Fill in "Method", "Old total cost", "New total cost", "Old quantity", "New quantity"; results are recalculated instantly as you type.

边际成本是什么？What is marginal cost?

多生产一单位产品所增加的总成本，MC = ΔTC ÷ ΔQ。成本函数可导时，MC 就是总成本对产量的导数。The extra total cost of making one more unit, MC = ΔTC / ΔQ. With a smooth cost function it is the derivative of total cost with respect to output.

边际成本和平均成本有什么关系？How do marginal and average cost relate?

MC 低于平均成本时，平均成本下降；MC 高于平均成本时，平均成本上升；两者在平均成本的最低点相等。When MC is below average cost, the average falls; when it is above, the average rises; they are equal at the lowest point of average cost.

企业怎么用边际成本？How do firms use marginal cost?

利润最大化的产量在边际收入等于边际成本 (MR = MC) 处。完全竞争市场中 MR 就是价格。Profit is maximised where marginal revenue equals marginal cost (MR = MC). In perfect competition MR is the price.

能举个计算实例吗？Can you show a worked example?

例如在「边际成本计算器（两点、成本表、成本函数）」中填 算法 = 两点，原总成本 = 1000，新总成本 = 1100，原产量 = 100，新产量 = 110，结果区显示：边际成本：10；总成本变化：100；产量变化：10For example, entering Method = Two points, Old total cost = 1000, New total cost = 1100, Old quantity = 100, New quantity = 110 in the Marginal Cost Calculator (Two Points, Cost Table, Cost Function) gives: Marginal cost: 10; Change in total cost: 100; Change in quantity: 10

哪些输入会被检查？Which inputs are validated?

「边际成本计算器（两点、成本表、成本函数）」会检查这些输入——「原总成本」：所选方式用到时必须填写，不能为负数；「新总成本」、「固定成本 a」、「b」、「c」：不能为负数；「原产量」、「产量 Q」：所选方式用到时必须填写，不能为负数，须为整数；「新产量」：不能为负数，须为整数；绝对值超过 10¹⁵ 的数也会被拒绝。不符合时结果区显示具体提示，不会给出数字。The Marginal Cost Calculator (Two Points, Cost Table, Cost Function) checks its inputs — "Old total cost": required when the chosen option uses it, cannot be negative; "New total cost", "Fixed cost a", "b", "c": cannot be negative; "Old quantity", "Quantity Q": required when the chosen option uses it, cannot be negative, must be a whole number; "New quantity": cannot be negative, must be a whole number; numbers above 10¹⁵ in absolute value are rejected too. When a value fails, the result area names the problem…

有哪些选项可以调整？What options can I adjust?

「边际成本计算器（两点、成本表、成本函数）」的设置：「算法」可选 两点、成本表、成本函数（默认 两点）；「原总成本」默认 1000；「新总成本」默认 1100；「原产量」默认 100；「新产量」默认 110；「产量列表」默认 0 1 2 3 4；「总成本列表」默认 100 150 190 240 310；「固定成本 a」默认 100；「b」默认 10；「c」默认 0.5；「产量 Q」默认 10。每次生成结果都按当前设置处理。Settings in the Marginal Cost Calculator (Two Points, Cost Table, Cost Function) — "Method": Two points, Cost table, Cost function (default Two points); "Old total cost" default 1000; "New total cost" default 1100; "Old quantity" default 100; "New quantity" default 110; "Quantities" default 0 1 2 3 4; "Total costs" default 100 150 190 240 310; "Fixed cost a" default 100; "b" default 10; "c" default 0.5; "Quantity Q" default 10. The result always uses the current settings.

计算结果可以作为最终依据吗？Can I rely on the result?

「边际成本计算器（两点、成本表、成本函数）」按标准公式计算，结果仅供参考；实际金额以银行、券商或税务机关的规则和四舍五入方式为准。The Marginal Cost Calculator (Two Points, Cost Table, Cost Function) uses standard formulas and is for estimation only; actual figures depend on your bank, broker or tax authority's rules and rounding.

「边际成本计算器（两点、成本表、成本函数）」免费吗？需要注册吗？Is the Marginal Cost Calculator (Two Points, Cost Table, Cost Function) free? Do I need an account?

「边际成本计算器（两点、成本表、成本函数）」完全免费，无需注册或安装，打开网页即可使用，手机和电脑都能用；输入的内容只在你的浏览器本地处理。The Marginal Cost Calculator (Two Points, Cost Table, Cost Function) is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.