[求助]这题该怎么做

helen_20jan

11.  The ABC Company wants to develop a simple inventory model for its raw material XYZ such that the total cost of placing orders and holding inventory is minimized.  The total cost (TC) equation is given as: TC=S*(D/Q)+C*(Q/2). Determine the optimum fixed order quantity Q that minimizes total cost function TC.

 

{Q=Sqrt(2*D*S/C)}

In the above equation, D is the number of units XYZ requires per year, S is the fixed cost incurred each time an order is placed with XYZ’s manufacturer, Q is the fixed order quantity – each time an order is placed, exactly Q units are ordered, Q/2 is the average level of inventory held by ABC Company in a given inventory cycle, and C is the cost per unit associated with holding 1 unit of XYZ in inventory annually.  Thus, S*(D/Q) is the annual cost of placing orders, while C*(Q/2) is the annual inventory holding cost.

helen_20jan

忘了说，红色字的是答案