Total Benefit

If the total cost curve is concave (before the inflexion point), C˝ < 0 and the cost increases at a decreasing rate. If the total cost curve is convex (after the inflexion point), C˝ > 0, and the cost increases at an increasing rate. At the inflexion point C˝ = 0. Global Minimum and Maximum. Global optimum occurs where f ′ = 0. ................
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