If you are a follower of this Casio 5800p Hub you may already know how to create custom formulas and functions and if so please share because I am eager to learn more.  I want to share with you what I have learned so far:

Here is a short tutorial on how to create a custom formula for the Casio fx-5800p. The fx-5800p has a library of 128 formulas ranging in various topics from geometry to physics and engineering. 

How to Create an Original Formula:

1. Press [ MODE ]
2. Select 5 for Programming Mode
3. Select 1 for New
4. Give a name, no more than 12 letters or numbers. Symbols are not allowed. 
5. At the File Mode screen, select 3 for Formula. 
6. Type your formula. Use the y=f(x) format. 
7. When you are done, press the [ EXIT ] key. 

Tip: You can use lower case letters, Greek letters, and stylized letters in the formula. Press [ FUNCTION ], then 4 for ALPHA to get access to these characters. 

Remember: Variables are one character length. The fx-5800p will execute implied multiplication when it executes two more consecutive variables. 

Running Your Original Formula:

1. Be in COMP Mode. (MODE, 1)
2. Press the [ FMLA ] button. Select 1 for the Original type. 
3. Select your formula, press [ EXE ] 
4. Use the arrow keys to enter values or scroll the formula. When you are ready to compute, press [ CALC ].