Closed-form solutions are attractive for two main reasons.First,
they allow researchers to develop analytical results that are
unattainable for models that must be solved numerically.For
example,classical results about the EOQ model,such as the
equality of the average ordering and holding costs at optimality,
the famous sensitivity analysis result,and the impact of changes in
the problem parameters on the optimal solution,depend on the
availability of closed-form expressions for the optimal order
quantity and its cost