marginalcost
Marginal cost is the increase in total cost when output rises by one unit. It can be defined as MC = ΔTC/ΔQ, or in calculus as dTC/dQ for continuous output. Since fixed costs do not change with output in the short run, marginal cost is determined primarily by changes in variable cost.
In many firms, marginal cost initially falls due to increasing efficiency, then rises due to diminishing marginal
A firm’s short-run supply curve is the portion of the MC curve that lies above AVC. Profit-maximizing
In the long run, all costs are variable, and the long-run marginal cost (LRMC) reflects the slope