Working with Member Formulas
You can define or edit member formulas directly in the Simplified dimension editor grid, in the formula bar, or in the Member Formula dialog where you can validate member formulas.
You can define member formulas to combine operators, calculation functions, dimension and member names, and numeric constants to perform calculations on members. Member formulas can also include:

Operator type, function, value, member name, UDA, and so on allowed in formulas.

Predefined formula expressions, including Smart List values, that expand into a formula or value upon database refresh.
To define or edit member formulas in the Simplified dimension editor: