HP 39gs VS TI-83 FEATURES & DIFFERENCES PART 2

[MATH] Menus

MATH function menus are common to all viable graphic calculators. The user must get to know the particular MENU layout and structure for the calculator model that they are using.

TI-83: Function menus are used throughout. The MATH menu provides a typical smorgasbord of the more common functions with sub menus. Some are superfluous (For example, log2x and 2x) others such as ABS should, like all the commonly used functions, be visible on the keyboard as a "key function".

HP 39gs offers an extensive library of functions with POLYNOMIAL functions exclusive to HP. The HP also offers a more comprehensive sub-library of many functions. For example: under the MATRICES functions a wide range of options are provided that are NOT provided on other models at this level. (For Example: Eigenvalues, Eigenvectors, Trace, Rank etc). It does not include the row operation functions. I feel these row operation functions are not really necessary and are incidental to the RREF matrix function. Once a function is used and in the HP 39gs HOME screen it can be easily copied, inserted and edited in further work. It is a simple matter using the copy key to build a bank of commonly used functions in, the HOME screen to enable easier entering of functions or operations. The access to the function menus in [MATH] is more consistent (and easier to access) on the HP 39gs than on any of the comparable models of graphic calculators.Solver function

Solver Function

On the TI-83: Press [MATH] Use [Up] or [Down] to select (0) Solver, Press [ENTER] Input your equation, and then press [ENTER] again. I feel the use of bounds etc only serves to complicate the process for students at this level. The HP 39gs does not include the notion of bounds. On the TI-83: The Solver must have the equations put in the form 0=. This is a weakness of the TI-83 and can introduce a source of 'student' error in sign when transposing. The HP 39gs is far superior in this respect and any equation is entered as it is stated. The TI-83 has no provision for assisting in a guesstimate (rough estimate) when using the solver. The HP 39gs at least has a crude plotter in the solve aplet which enables reasonable guesstimates to be made for the initial value to be used in the solver.

Complex Numbers

The TI-83: Calculations don't automatically revert to complex mode when complex numbers occur in a calculation (For example, Square Root (-4) if encountered in solving a quadratic equation will give an error message). You must first put the calculator in the complex mode using the [MATH] menu, otherwise you will get an error message. Complex mode for number calculations is not automatic Once in the complex number mode you can do computations using complex numbers and also the usual (Real, Imaginary, conjugate, Modulus, and argument). On the HP 39gs, if complex numbers occur during a calculation the HP 39gs recognises this an automatically puts all the results associated with that calculation in the complex form (a,b).