# Fun Features of the TI-84+ Family

Recently, I was a panelist for a TI Calculators Webinar that happened to follow a new Operating System release for the TI-84+CE color calculator and its accompanying Apps and computer software.  The new calculator features were not our primary focus, but since OS 5.3 was just released, we tried to highlight them when appropriate. This post summarizes a few features of the new OS version 5.3; I want to share in more detail these fun features that will help my teaching and my students.

1.New shortcut key for the fraction template. I use the fraction template    to make the calculator inputs match the math notation.  It has been available for the entire TI-84+family for several operating systems.  Press ALPHA-Y1 to access the shortcut menu for the fraction and mixed number templates. On the color versions of the TI-84+, it is also found in the MATH>FRAC menu.

And now, there is an even faster way on the TI-84+CE: press

2. Piecewise Function Graphing now allows entry that looks like the textbook! Press MATH and select B. piecewise. Choose the number of pieces and then enter them using the inequality operators in the TEST menu (2nd MATH) or the CONDITIONS submenu.  Discuss with students whether it matters which piece comes first in the piecewise definition.

You might notice that in Y= the viewable area is limited when entering a piecewise function.  If desired, you can enter the piecewise function on the Home Screen and store it to one of the graphing function variables.  You will need to start and end the piecewise function with the quotation symbol (press ALPHA and the PLUS button).

Don’t have a CE but want to graph piecewise functions?  Instructions are found HERE and this method can prompt a rich discussion of how to use a logical operator in a math expression (the inequality statement will represent 1 if it is TRUE and 0 if it is FALSE).  Try TRACING the piecewise graph.  Where does the Y-value exist and not exist?

I like using piecewise functions on the calculator: it enables a graphical confirmation of a complicated algebraic expression, and that helps my students build their understanding.  It also gives us access to many real contexts for problem-solving.

3. Updated Transformation Graphing App. The newest Transformation Graphing App allows TWO transformable functions in Y1 and Y2 plus you can graph other static functions in Y3 to Y0 and up to three StatPlots.  You still use the four parameters A, B, C, D and you can now access several stored parent functions for lines, quadratics, cubics and trigonometry.

I like to challenge students to “Match the Graph” with a static function graph whose equation I haven’t shared (see below left, can you transform the blue graph to match the pink one?).  Or put data in a StatList and transform a function for a best fit curve.

It is now easier to move back and forth between the graph and the SETUP screen, and the “TrailOn” feature has moved to this more logical location [it was available in prior versions of Transformation Graphing, accessed from the FORMAT menu by pressing 2nd ZOOM.] See above right for the trail of quadratics.

And the entire Transformation Graphing process is faster than it was before (be patient if the calculator seems slow to respond and check for the “busy” indicator in the upper right corner of the color calculator screens).  HERE is a “How To” file for the Transformation Graphing App.

4. Easy storage of a Tangent Equation. When drawing a Tangent line to a graph, a MENU can be accessed using the GRAPH button (before entering a point of tangency) to store the equation directly to Y=.  This makes it easier to examine the equation of the tangent line in relation to the equation of the original function.

Entering the X-value for the point of tangency can be done by entering a value with the numeric keypad, or tracing to the desired point.  I prefer using the ZOOM DECIMAL window for “friendly” trace increments.

5. Finally: updating to a new OS is easy. You need a USB-calculator cable or a calculator-to-calculator cable.  Instructions are HERE and the OS is a free download from the TI WEBSITE.  Use the (free) TI-Connect™ CE Software or link to an already updated calculator.  For the new OS 5.3 for the CE calculator, there is a “Bundle” file that updates the OS and the Apps at the same time.

*Keep in mind that all the feature enhancements have alternatives for older OS versions. And even if your classroom has a mix of TI-84+ family devices, the TI-SmartView™ emulator computer software displays 3 distinct environments, so you can demonstrate in the CE emulator to take advantage of the features for the whole class.

6. Save Emulator State is back!! (I almost forgot to mention this) The TI-SmartView™ CE software NOW has the ability to “Save Emulator State” so the teacher can save work where you are when the bell rings at the end of the period and you can open it back up when that class returns the next day.  Or you can prepare your SmartView calculator in advance with your functions, lists, programs, etc. so that everything is loaded efficiently when you need it.  Instructions are HERE for using Emulator States.

Enjoy the new and old fun features! Reach out to me if you have any questions.

Resources:

The  “Making Math Stick” Webinar On-Demand is HERE and the activities discussed are HERE.  The new calculator features were not our primary focus, but since OS 5.3 was just released, we tried to highlight them when appropriate.

A great summary of some not-so-new features of the TI-84+ Family was written by my webinar co-panelist John LaMaster and is found HERE.