“…with M > 0 a given constant and u g is the corresponding solution of the elliptic variational inequality (1.3) associated to the control g. Several continuous optimal control problems are governed by elliptic variational inequalities, for example: the process of biological waste-water treatment; reorientation of a satellite by propellers; and economics: the problem of consumer regulation of a monopoly, etc. There exist an abundant literature for optimal control problems [4,42,50], for optimal control problems governed by elliptic variational equalities or inequalities [2,3,5,6,7,8,9,11,19,20,26,28,30,32,34,38,40,45,46,52,53,54], for numerical analysis of variational inequalities or optimal control problems [10,13,14,15,16,17,21,22,23,24,25,27,33,35,36,37,43,47,48,49,<...>…”