Before programming, here are solutions to graphing problems that frequently occur.  This is a solution sheet for the TI-83/84This is a solution sheet for the Casio fx-9750/9860.

You can create programs on your calculator to simplify some repetitive or frequently used tasks.  I am only covering TI-83/84 Plus and Casio fx-9750/9860.  The Casio is a good alternative to the TI because it is cheaper, but it is harder to find stores selling them in Canada; it is easier to purchase them on-line.  For my class, the fx-9750 is sufficient and sells for \$69.99.  The TI-84 Plus is about \$139.99.  The TI-83 Plus is discontinued but if you look hard, you may still be able to find one for about \$129.99.  It is very important to stick to my recommended models because it is impossible for me to find time to figure out how to use different models.

If you want to learn how to program, here is a site for the TI.  The site for Casio is not as good, but here it is.  Remember to start out small and work your way to larger projects.  It also helps to look at a lot of sample programs to see how other people create code.  Logic is one thing that you will have to master.

If you find it too tedious to program your calculator, you can download the programs on to a PC, then transfer them to your calculator.  Here's how to do it for your TI, and here's how to do it for your Casio.

It can be a daunting task learning how to get all the functions, but you can always use the catalog feature if you can't use the navigation buttons; the catalog will list all the functions in alphabetical order; just use the alphabet keys to quickly scroll to your function.  You may want to Google the functions to correctly code the parameters and check exactly what the functions do.  Even though a function may sound like it gives you what you want; you want to make sure so that you don't spend hours debugging your program.

The factoring quadratics is a frequent operation.  If you're not sure whether it factors evenly (integers), just use the quadratic formula.  Remember that you need to check the discriminant to see if it is factorable or if there is a double root.  Here is the TI program.  And here is the Casio program.  If your program is not functioning properly, carefully compare the listing with what you have entered.  The Quadratic Formula is first used in PreCalc 11.  Here is the downloadable TI program.  And here is the downloadable Casio program.

## Factoring

Along the factoring theme, you will need to be able to completely factor whole numbers.  So here are a subroutine (FACTSUB) to factor and two small programs that use the subroutine:  FACTORS and ISPRIME.  ISPRIME will tell you if the number is a perfect square in the case where it is not prime.  Here is the TI program.  And here is the Casio program.  Factoring is first used in Math 8.  Here are the downloadable TI programs: FACTSUB, FACTORS, ISPRIME.  And here are the downloadable Casio programs: FACTSUB, FACTORS, ISPRIME.

## Factoring Polynomials

You can use graphing to find the zeros of a polynomial or you can use this program that uses the factor property.  The zeros are stored in List 1 and the possible factors are stored in List 2 and 3.  Here is the TI program and here is the Casio program.  This program is for PreCalc 12.  Here is the downloadable TI program.  And here is the downloadable Casio program.

## Remainder and Modulus

Here are two more useful functions: remainder and modulus.  The Casio has the modulus function built-in but it only accepts integers.  These two functions will accept decimal values.  Here is the TI program and here is the Casio program.  Remainder and Modulus can be used anytime after the student learns about remainders.  This can be used at any grades but is meant for PreCalc 12.  Here are the downloadable TI programs: REM, MOD.  And here are the downloadable Casio programs: REM, MOD.

## Newton's Method

Newton's method is used to find zeros in Calculus I.  Here is a very short program that makes iterations less painful.  Here is the TI program and here is the Casio program.  Here is the downloadable TI program.  And here is the downloadable Casio program.

## Rectangular Approximation Method

RAM is used to find the approximate area under a curve by using equal partitions.  Since the graphing calculators find a fairly exact value, you need this program to do rougher approximations.  Here is the TI program and here is the Casio program.  This program is for Calculus II.  Here are the downloadable TI programs: RAM, RAML.  And here are the downloadable Casio programs: RAM, RAML.