TOTAL COST AND MARGINAL COST: A mathematical connection between marginal cost and total cost stating that marginal cost IS the slope of the total cost curve. If the total cost curve has a positive slope (that is, is upward sloping), then marginal cost is positive. Moreover, if the total cost curve has a positive and increasingly steeper slope, then the marginal cost is positive and rising. If the total cost curve has a positive and decreasingly steeper slope, then the marginal cost is positive but falling. See also | total cost | total cost curve | marginal cost | slope | law of diminishing marginal returns | total-marginal rule | total variable cost |
