In the current world, we are all living in; mathematical calculations are everywhere. They are in businesses, schools, constructions, accounting offices, and design among others. Some of these calculations are hard enough to a point they cannot be done manually. Calculators are very crucial most likely scientific ones. The scientific calculators have got functions and calculations that some other calculators cannot perform. Common calculators do simple tasks like addition and division, but the complex ones do even algebraic equations and graphs like the Yi-Nspire CX calculator. Due to the many functions available, the calculators are most suitable in environments where there are a lot of complex and graphical mathematical calculations going on like the colleges and areas of higher learning.

The TI-inspired CX CAS is one of the latest graphical calculators manufactured by the Texas Instruments Company (Davis, 2015). It is one of the advanced ones since it is an improvement of the other versions of the same company. The CAS means Computer Algebra System. It is a unique feature available on this machine that can handle a lot of mathematical equations that are tedious and difficult if handled by the human brain. The best part is the calculator’s answers are in the exact number form excluding a case where the decimal is required. There are other features also related to the calculator; they include applications that can draft shapes, analyze and collect data, make spreadsheets and all elements involved in statistics. It is designed like a mobile with a rechargeable battery, slim design, and a colored interface which makes it look great.

Such as alternate new calculators crazy there, the NSpire cx CAS offers a rechargeable battery (Flores, 2015). Same time some models for graphing calculators utilize four AAA batteries, this version gives you accuse through a supplied cord, comparable with an iPhone or iPod. The majority of understudies say that person accuses might most recent up to a month for general moderate utilization of the number cruncher.

**Battery for longer use**

The calculator has some of the best features hence a great advantage (Thompson, 2016). Coordinated circuit math templates tolerance people to enter expressions Furthermore see math symbols; formulas also stacked portions in the same way that they need aid printed over textbooks and on the board. The interesting Chem box characteristic gives scholars undoubtedly information on compound formulas Also equations.

Use natural drop-down menus to explore through the TI-Nspire™ cx CAS handheld. Make documents save your worth of effort likewise mainly concerning illustration opening, altering and storing files looking into a workstation.

There are some downsides though of the calculator. The user interface of the machine is document based. This means that it is less user-friendly since you can’t find everything on the screen at the same time. The other demerit is that its programming capacity is not as strong compared to the calculators related to it.

Making a program is more monotonous than we might suspect it must be. You begin by making another record and after that inside that archive start another program or capacity. When you make another program, you can alter it like the way you change on a TI-84/83 by choosing charges from menus. In any case, there are way fewer charge alternatives, and they forgot probably the most vital ones, similar to menus. The programming dialect itself is likewise a marginally unexpected form in comparison to it is on the TI-84/83 models. Along these lines, at last, this exceptionally just abandons you with one choice. That is making a program that takes in a handful of numbers and afterward in a split second yields an outcome (Stewart, 2015).

Overall you can’t get to the program from any screen or report aside from the one, you made it in. So implies on the off chance that you are doing counts on the adding machine screen you can’t merely rapidly run a program and after that backpedal to what you were doing. You need to leave the number cruncher screen and afterward open the archive with the program and run from that point.

**How the calculator looks.**

**Calculator usage**

**Turning on**

For the calculator to function, it must be turned on using a button.

From the above picture, there is on a button on the right side. If pressed the screen goes to the home screen by default then one is ready for any calculations related to the calculator. The handheld is on as the load of the operating system.

**Turning off**

On the same button, there is the off symbol. There is no off button so you have to click the control button plus the on the button to turn it off and the memory is wiped.

#### Starting the calculator for the first time

As explained above, to begin, there is charging the battery and then powering the handheld on and off. There is also another important feature that helps in conserving the battery for a longer period. It is known as the automatic power down. The APD button allows the calculator to power off after three minutes of inactivity. The advantage of this is that the memory is not wiped. One will go to the last activity that was in progress and continues. To alter the power settings, one should click “on”, 5, and 3 to go to the handheld setup.

If it is the first time dealing with a computer, there is a need of adjusting the language according to what a person understands. It is done after the loading of the OS. There are different languages which include both English US and UK. After selecting, one should press ok and then be ready to start (Mickle, 2015).

The display is important hence the font size should be adjusted according to the user (Urban-Woldron, 2015). One should navigate to font size, open the dropdown menu and choose the preferred size, and press enter to select it. There is also the screen brightness. To add the light, long press the control button then tap the + button, and to reduce do the same but tap the – button.

**Touchpad**

The touchpad, as shown above, can help one navigate since it has up, down, left, and right together with an enter key. The touchpad works in two ways though. One is by using it like a mouse by using the fingers in a sliding motion to move the cursor to the point of destination and tap at the center to select an option. The second option is by using the arrows to move the pointer and then click enter or tab to complete the action. Also, note that the touchpad can also be customized according to what the user wants. The pointer can be set to move fast or slow among others.

**Scratchpad**

A scratchpad application acts as a shortcut to doing calculations while at the same time working on a document. If a calculation needs to be done immediately without affecting the document, one opens the scratchpad, does the calculations, and later either discards without modifying the document or adds the calculation to the document.

**Using the home screen**

It is the starting point of all activities to be done on the handheld (Gallegos, 2015). The activities are done here include:

- The opening of the scratchpad to do mathematical calculations
- Creation of new documents
- Management and reopening of other existing documents in the memory
- Settings management and status viewing
- Accessing the hints for operating the handheld
- Retrieving new documents
- Going back to the newly opened document

Something to note is that to return to any place or home screen, one needs to press on.

**There are some home screen options**

- Scratchpad: As explained earlier, it is used to navigate between calculations and the document being worked on at the current moment. It is divided into two though
- Calculations: to open the scratchpad with an active calculator one just clicks A from the home screen. These give access to the user to do any calculations that the calculator can. From all simple calculations to powers and roots, algebraic calculations, logarithms, and more.
- Graph: to activate the graph, at the home screen one types B and the graph is active. From this, one can do any graphical calculations involving the x and y-axis and more.
- Documents: to activate these, one just uses the associated numbers or uses the touchpad to select a specific icon and later press enter or tab on the touchpad. There are various types of documents.
- New document: it opens the calculator’s document associated with the available applications
- My documents: it opens existing documents that were saved or some files that were sent to others
- Recent: this opens the list of the five most recent documents which were saved of late.
- Current: as the name suggests, it opens the document that is open at that immediate time.
- Settings: it checks the handheld status and also settings change.

Application icons: a user might need to add a new page to an ongoing document, he/she needs to click the application icon, and if there is no current document, a document opens with the current application which has been activated at the new page. There are different kinds of these applications as explained below

- Calculator: if clicked it adds a page to the doc where mathematical expressions can be entered and be evaluated.
- Graphs: if the icon is clicked, it adds to the page the exploring options and graphing properties
- Geometry: the icon adds a page to the document where geometric shapes can be created and explored.
- Spreadsheets: the icons add tables where tables can be added data and be analyzed and interpreted.
- Statistics: this is an important icon that adds the needed tools for the visualization of data sets about different plots. It also gives tools for data manipulation so that relationships between sets of data can be explored.
- Notes: the icons help in txt addition to the current documents being active. This help when it comes to sharing with other users also.
- Vernier Dataquest: the icons help in collecting and immediately analyzing the data from instruments like probes and sensors.

#### The handheld screen functions

Every icon in the above handheld screen has its functions. The icon and its functions are described below.

1. Page scrolling arrows: the user can use the touchpad together with the arrows to scroll through the document pages. Its fast and an essential function in the calculator since navigation is a must in all devices to be user-friendly.

2. Page tabs: its use is to show the problem number which is followed by the page number. If the user moves the pointer to the tab where problems are named, it is programmed to display the page name.

3. Document name: it is functioned to show the document name and also shows the changes that were made when the document was altered last by the user.

4. Press to test. It indicates that the handheld is in a mode of the press to test

5. Login shows the login status of the handheld. It can either be loaded to get an access point which is known as blinking state, solid id it has found an access point, it is not communicating, can be ready for login, or can be logged in and also charged which is indicated by a solid arrow. The user should click the icon to see his/her login status here.

6. It involves the shift, CAPS, and CTRL status.

7. Status and the setting: the icon if clicked shows the battery supply level status and also the user can change the settings from here.

8. Close document: as the name suggests, if the user clicks the icon the current document would be closed. If the user has not saved, he/she will be prompt to discard or save the changes. It uses an operating system and hence has almost similar features to those of a desktop or a laptop.

#### Hints

Hints are quick shortcuts that help the user to do specific functions faster and without a lot of complications. They are available at the handheld software. There are very many ways one can access hints in the calculator. They include

- Pressing CTRL and TRIG buttons
- Some dialog boxes have question marks in them, the user should just click the icon, and the hint will be opened for that specific task.
- So that the user can scroll down the hints, arrows or the touchpad should be used.
- So that one can page down, use CTRL 3
- For paging up, use CTRL 9
- So that the user can navigate up to the end of the hints list file, use CTRL 1
- To go back to the start of the hints file just press CTRL 7

From those tricks, the user can get all the hints desired to make the work easier while using the calculator (Loe, 2018). It is the reason why the handheld is very important together with the touchpad in the device. If the user doesn’t know how to use the two, then it would be hard to use the calculator.

**Using the scratchpad**

It is a feature of the handheld as discussed earlier that helps in mathematical expressions and graphical functions.

One should press the menu so that one can view the scratchpad calculate/ graph menu. All are under the geometry applications as discussed earlier.

To close the scratchpad one just clicks ESC and it is done. Everything is simplified and designed similar to other devices people hence making the calculator such a friendly one.

**Calculations**

Using the scratchpad, one enters a mathematical expression at the entry line and then clicks enter to give the solution to the equation (Klecker, 2015). The answer is always displayed according to standard mathematical notation as the user inputs.

After each answer, the results are saved in the scratchpad history which is displayed above the entry line. The results format can also be customized by the user. The results may be set to be in one decimal place and such settings.

**To insert items into the catalog**

The user can enter functions, units, and commands in the catalog into the entry line. To do that:

Open the catalog which will list all the controls and the functions from A to Z.

If the user finds the function, next, he/she will select it by pressing enter to insert it into the equation.

If the functions are not visible to the user, then press a letter of the function to go to the direct location where the function is. The letters used are the first letter of the function to be used.

**Templates**

The use of these templates is to help the user enter system of equations, derivatives, matrices, products, piecewise functions, and more mathematical expressions.

The best way of inserting these expressions other than using the manual method is using a wizard. The wizard has got boxes that help the user enter the required arguments in an expression.

**Viewing the history**

As indicated earlier, every mathematical expression and its result becomes part of the scratchpad history by default. It is always displayed on top of the entry line.

The user should press up or down buttons so that he/she can go through the history.

**Copy the history to the entry line**

- There is a method in this device in which one can copy the history data back to the entry line.
- One should first go through the data using the up and down keys and choose the data to be copied.
- Another option is can select part of the data like the results by using SHIFT and the arrows.
- Lastly, click enter to copy the data and then insert it into the entry line, and it is done.

**Clear History**

Hen history has cleared all variables and functions to adapt to the current value at that time. There is a method to undo though by the undo feature. To erase the memory, one should go to the actions menu and select clear history.

**Edit expressions from the scratchpad**

Results from the history cannot be edited, but one can use a trick by copying the data into the entry line and editing the expression from there. To select the expression just use arrows to start the place to copy and the other indicator either left or right and then select enter to copy and then copy it to the entry line. It is that simple.

**Graphs calculations with scratchpad**

From the scratchpad graph page, the user should click the expand button in the entry line and then type the expression to start the graphical calculations. The process is:

- The user should choose the graph type from the menu and select it. E.g., to graph a function, a user clicks menu and three then 1. After selecting, the entry line changes so that it can display the graph type which has been specified by the user.
- Then the user should type an expression together with other parameters for the graph to be complete.
- Then press enters to graph the written function or press the down key arrow to add another feature. The viewing area can also be customized from the menu button.
- After graphing, the user can use the menu key to navigate and analyze the graphed function by assigning a given variable or tracing it and also locating points of interest.

**Function table display**

The table of values can be displayed by pressing menus, 2 and 5.

The same table can be hidden by first having a click on the graph and then pressing menu two then 5.

**Changing axes appearance**

Working with graphs, the axes known as Cartesian are shown by default but can be customized by the user according to her/his preferences. The process is:

- The user to press menu and 4 and select the tool to zoom.
- Then choose the axes and press CTRL, menu, and 3 to activate the attribute tool.
- Axes scale adjustment plus tic mark spacing to be manual.
- Double click the end values of the axis to change them and type new values.
- Axes location adjustments
- Press menus, 4 and 1 to change the axes scales
- Press menus, 2 and 1 to hide or display axes.

**Point of interest**

The user can use the tools to analyze the graph menu so that one can find the point of interest in a particular graphed function. One can use the tool to find minimum, zero, or maximum, derivative, point of intersection, and inflection.

**Working with documents**

All the work done in this calculator is saved in the documents and can be shared with other handheld users plus those using similar software. There are some divisions though. Each document is divided into one to 30 problems which are also separated to one to fifty pages and are also shared to a maximum of four work areas.

**Working with applications**

It involves the creation of a new document and application selection. There is also the addition of a new page and an application that can open the document. There is also the addition of multiple applications on a page of a report.

In conclusion, the TI-Nspire CX Graphing calculator is the best when it comes to all kinds of mathematical expressions and graphical functions. The interface is an excellent, extended-span battery with a problem only in programming areas. Any sector can make use of the calculator, but most likely it can be used best in areas of data collection statistics. Would recommend this kind of calculator to students who deal with complex graphs and calculations.

#### REFERENCES

Davis, J. D. (2015). Prospective mathematics teachers’ interactions with CAS-based textbook elements. The International Journal for Technology in Mathematics Education, 22(3), 107-114.

Flores, Á. H., Gómez, A., & Chavez, X. (2015). Using TI-Nspire in a modelling teacher’s training course. The International Journal for Technology in Mathematics Education, 22(2), 79-84.

Gallegos, R. R. (2015). A Differential Equations Course for Engineers Through Modelling and Technology. In Mathematical Modelling in Education Research and Practice(pp. 545-555). Springer, Cham.

Klecker, B. M., & Klecker, R. L. (2015). Equity of Student Use of Graphing Calculators for Mathematics Learning and Assessment. Online Submission.

Loe, S. B. (2018). U.S. Patent Application No. 15/360,737.

Mickle, A. D., & Clarke, P. A. J. (2015). Paper 2: Using TI-Nspire to Engage Preservice Mathematics Teachers in an Exploratory Geometry Module.

Stewart, J. (2015). Single variable calculus: Early transcendentals. Nelson Education.

Thompson, L., & Jones, G. (2016, December). MATHS ACTIVITIES FOR STUDENTS WITH SPECIAL NEEDS. In 2016 MATHEMATICAL ASSOCIATION OF VICTORIA’S ANNUAL CONFERENCE PROCEEDINGS (p. 5).

Urban-Woldron, H. (2015). Motion sensors in mathematics teaching: learning tools for understanding general math concepts?. International Journal of Mathematical Education in Science and Technology, 46(4), 584-598.