A complex function of three variables is created icon of the calculations expandable bar (third from the bottom).
Such a function may be modified through icon .
For instance,you can define a real function of two variables by f(u, v, w) = 2u²v + 3Im(w). Enter f for the name, u and v and w for the variables names and 2*u^2*v+3*Im(w) for formula.
See also : Complex calculus syntax.