Regions nonfeasible

When a system is constrained, the factor space is divided into feasible regions and nonfeasible regions. A feasible region contains permissible or desirable combinations of factor levels, or gives an acceptable response. A nonfeasible region contains prohibited or undesirable combinations of factor levels, or gives an unacceptable response. 

Give definitions for the following maximum, minimum, optimum, unimodal, multimodal, local optimum, global optimum, continuous, discrete, constraint, equality constraint, inequality constraint, lower bound, upper bound, natural constraint, artificial constraint, degree of freedom, feasible region, nonfeasible region, factor tolerance. 

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