Example 1  define a polynomial then plot in Function AppSay you wanted to define and plot an expression AX2 + BX + C where the coefficients A,B and C can be adjusted by you as needed. The following will define a new expression:
Shift Define ALPHA ALPHA^{[1]} polynom_ABC Enter ALPHA X x2 × ALPHA A + ALPHA B × ALPHA X + ALPHA C Enter Then check all the variable boxes  if not already checked OK. 
There is now a new expression polynom_ABC saved in Toolbox/User/User Functions. Note the order of the variables (X,A, B, C). This is important when using this definition later.
Now, open the Function App, Symb view. In the top function F1(X)= insert the new polynom_ABC function. Key in the coefficient values for (X,A, B, C) using X, 1, 1 and 1. Finally, you can use copy/paste to enter this function in F2(x) through F6(x).
Symb Toolbox User Functions polynom_ABC X , 1 , 1 +/ , 1 OK Click on F1(x) inputbox Shift Copy Click on F2(x) inputbox Shift Paste 1 OK 
Your Function App Symb screen should look similar to below. You can use your own values for A, B and C if you wish.
To plot these values, press the Plot key. The curves shown below are F1F6. If you want to see how other A,B,C coefficients affect curve(s), simply return to the Symb view and edit the coefficients.
