This message is generated when the first argument in ConstrainedMax or ConstrainedMin is not a linear function of the indicated variables or when the coefficients are not real numbers.
ConstrainedMin and ConstrainedMax are designed to handle minimization and maximization of a linear function subject to linear constraints.
Off[message] switches off the message; On[message] switches it on. For example: Off[ConstrainedMax::cmfun].
Examples
Basic Examples(1)
The first argument is not a linear function of the variable: