## Graphing Calculator Review

### Why Buy a Graphing Calculator?

Whether you're trying to get a grade to be proud of on that next algebra test, helping students better understand mathematical problems in the classroom or designing a blueprint for a mechanical device, finding the right graphing calculator can help. There are three major brands vying for your attention: Texas Instruments, Hewlett-Packard and Casio. At first glance, each of these calculators appears very similar. Dig a little deeper, though, and you'll find that each one has unique features that set it apart.

In this buying guide, we break down the features of some of the most popular graphing calculators and help you answer some basic questions. What are the different types available? Which are permissible on the ACT and SAT? Which ones are easy to use? Choosing the right one doesn't mean finding the one with the most features; some may offer things you don't need. We'll present you with info on many popular models and let you decide which one best suits your particular needs. You can also visit our Learning Center for articles about Graphing Calculators.

## Types of Graph Calculators

Finding the right calculator to help you solve mathematical and scientific equations in the classroom or at work depends on the features you might need. First, understand that these are different from scientific calculators, which offer an easy way of finding answers to basic equations. Scientific calculators typically have smaller screens than graphing calculators do, and they perform basic scientific notation, trigonometric, exponential and logarithmic functions.

While the biggest difference between a scientific and a graphing calculator is the screen size, other features, such as graphing capabilities, color displays, and the ability to write and store algorithms and programs set graphing options apart from scientific ones. Graphing calculators can also be used for drawing scatter plots, calculating probability and creating tables.

### CAS vs. Non-CAS Models

There are two different kinds of graphing devices available: Computer Algebra Systems (CAS) and non-CAS. Both CAS and non-CAS calculators include advanced features that let you manipulate variables and solve equations. Some non-CAS versions, however, are suitable for only basic math problems.

One of the biggest differences in using these two types of calculators is how they display an equation. CAS calculators let you enter variables and then simplify them into a format known as Pretty Print or Natural Display. The result is a mathematical equation similar to what you see in textbooks. Pretty Print often makes an equation easier to understand for both students and teachers. Calculators of this type are also capable of evaluating symbolic expressions, making them useful for scientists and professionals. The addition of this capability also increases the price of the calculator. Non-CAS graph calculators display expressions in syntax format but are usually less expensive.

### RPN vs. Algebraic Modes

If you use your graphing calculator or scientific calculator for advanced calculations, you may want a choice when it comes to the type of mode you use to input equations and functions for electrical engineering, chemistry, physics and even astronomy. There are two basic modes: algebraic and Reverse Polish Notation (RPN.) Most calculators use the algebraic input method, which uses the order of operations in a way naturally taught to students by professors in school.

Some, like the HP 50g, give you the option of using RPN. RPN makes complex calculations easier by removing the parenthesis and brackets in the equation. It then places the calculation in the correct order of operation. This saves steps and reduces the amount of storage space each calculation uses.

### Online Options

**What About Online Graphing Calculators?**

A cost-saving alternative to a hand-held calculator is an online version. There are many available, both free and with paid subscriptions. Some, such as the Calculator+ app, are free but require a small purchase to unlock all modes, while others, such as Tydlig, have upfront costs.

One of the most popular free online options is the Desmos graphing calculator. Students, professionals and teachers can use this application on PC and Mac as well as Apple and Android devices such as tablets or smartphones. The application lets you plot tables, graph functions and find quick answers to equations. You can also create an account and save your past equations.

There are drawbacks to using a free or paid online graphing calculator because internet access is necessary at all times and not all are capable of handling complex equations. You also need a computer, tablet or smartphone when using the graph calculator online, and these are often banned from testing sites and in most classrooms.

**Common Graphing Calculator Apps**

Both CAS and non-CAS calculator graphing options, like the TI-Nspire CX CAS, the TI-84 Plus and the Casio FX-9860GII S, include apps that make learning, teaching and working easier. Some devices include NoteFolio, which lets you use the calculator's keyboard to take notes in any class and transfer them to Microsoft Word files. StudyCards is an app that lets you create digital flash cards for any class – even those not related to math or science. Many calculators also feature LearningCheck, an app that lets students and teachers create their own review questions and practice tests and share them with others. There's also the Spreadsheet app, which lets you analyze statistics using rows and columns and the eActivity app, which helps teachers create discovery-based lessons for their students. While many graphing calculator apps come preloaded, most calculators are compatible with additional applications.

### Tips For Students

Many calculators provide similar functions, but not all provide those needed for every course you take in high school or college. Some, like the TI-83 Plus, are appropriate for courses like pre-algebra, algebra, trigonometry, business and finance, and AP calculus. However, other graphing calculators, like the TI-Nspire CX, TI-84 Plus or TI-89 Titanium, tackle the needs of these courses and are also better suited for geometric calculations, like finding the area of a triangle using Heron's Formula.

Some calculators work well for high school classes, but these may not always translate well into college classes. When looking for the best graphing calculator for your needs, pay close attention to what the calculator does. Basic options for high school courses like algebra and statistics may not offer functions for creating scatter plots, finding absolute values or basic graphing.

In addition to these capabilities, advanced graphing calculators offer other scientific and mathematical functions, like graphing derivatives, finding the min and max, and comparing exponential and power dispersion. These capabilities are necessary for advanced high school and college courses.

Before purchasing any graph calculator as a student, always check with your school and see what devices they allow in the classroom. Some schools don't allow certain advanced versions. Due to their popularity, many classes allow Texas Instrument calculators. Also, consider whether the graphing calculator is usable on AP tests or standardized like the PSAT, SAT, ACT, IB or Praxis. As of this writing, using the TI-83 Plus and Casio FX 9860GII S on the ACT and SAT is acceptable, but the TI-Nspire CAS and HP Prime are not permissible for most exams.

### Tips For Teachers

When using calculator graphing devices in the classroom, teachers must understand how the calculators work. Many brands offer excellent resources that help teachers learn the functions of these devices, and they offer ideas for using the calculators in the classroom. Such resources include:

- Pre-planned activities and lessons
- Instructor-taught courses and webinars
- Easy-to-understand materials

Texas Instruments offers a ViewScreen panel product. This product works with an overhead projector to enlarge your TI calculator screen while you teach. You can project the image of your screen onto a whiteboard or projection screen, so your students can see and understand the calculations you input as you teach the concepts.

Some brands also offer free software trials that let you explore how the graphing calculators work before making a purchase for your classroom. The software emulates a hand-held calculator and lets you perform all the same functions the device would.

For teachers purchasing 2D and 3D graphing calculators for the classroom, cost-saving options are often available. You may have the option of buying a bundle of calculators from a retail or store distributors at a lower cost than the individual price. Many calculators intended for classroom use also come with colored cases and sliders. This makes distinguishing between student-owned and school-owned calculators easy.

### Graphing Calculators: What to Look For

When looking for the best graphing calculator, consider everything from the display to the memory to software integration. Here are a few elements you should look for.

**Display**

The most basic graphing calculators offer large LCD displays, with many featuring backlit screens for ease of viewing. Some have high-resolution color displays, like the Casio PRIZM FX-CG10, that let you quickly see the difference between two similar graphs by formatting one as orange and one as blue. Character displays – or the number of characters and lines you can see at one time – vary among calculators. The TI-84 Plus, for instance, features an eight-line by 16-character display, while the Casio PRIZM has an eight-line display, and each line displays a max of 21 characters.

**Processing Speed & Memory **

Two of the most important elements of a graphing calculator are memory and processing speed. Fast processors let you perform and save equations quickly. Texas Instrument calculators boast ARM, Zilog Z80 and Motorola 68000 processors with different speeds, measured in megahertz (MHz). Advanced calculators, especially CAS versions, typically feature faster processors.

Many graphing calculators let you save equations, solutions and common problems for later using the integrated memory. The capacity for each calculator varies. For instance, the Casio FX-9860GII S boasts 64KB of RAM and 1.5MB of ROM, and the TI-Nspire CX CAS has 100MB of RAM and 64MB of ROM.

All calculator graphing devices operate using batteries. To avoid having to replace the batteries frequently and reduce the chances of the calculator dying in the middle of your class, consider a graphing calculator with rechargeable batteries. Many come with USB cables that connect to any USB-compatible device for charging low batteries. You can use these rechargeable devices with optional wall chargers or docking stations as well.

**Ease of Use Features **

Whether you use graphing calculator professionally or in the classroom, look for features that make using them simple. Some have touchscreens or dedicated buttons that let you quickly switch to different views or programs. To save you time, others let you program keystrokes and shortcuts. There are even some that offer split-screen views, which let you see multiple graphs or equations at the same time.

For quick use, options like the TI-Nspire CX CAS and HP 50g come with built-in equation libraries. These programmable libraries let you select from thousands of common equations. Most also feature functions that help with complex graphing and calculations, such as:

- XY-lines
- Absolute value
- Min and max
- Tables
- Mean, mode and medium
- Factoring

Some, like the Casio PRIZM, integrate real-world connections by letting you use pictures with your equations. By overlaying equations or graphs onto the pictures, you may more easily understand the problem you're solving.

**Other Helpful Features **

3D graphing calculators help you better understand the way functions work by displaying them in 3D. These models let you choose the steepness and height of your 3D graph, alter the colors of various sections and create several different 3D graphs using the same axes.

Many graph calculators come with USB cables that let you connect the calculator to a computer or compatible device. This makes sharing files between devices easy. Most let you integrate equations into Word and spreadsheet programs.

A USB cable also lets you download updates and new applications. Even some basic calculators designed for middle-school use, like the TI-83 Plus, feature USB cable compatibility for updating the software and operating system for extended use in later school grades.

**Price & Resale Value **

Graphing calculators vary in price, with some as low as $50 and others in the $150 range. The cost of the calculator greatly depends on whether it's a CAS system and the features it has. If cutting costs is a priority, consider non-CAS systems and calculators that come preloaded with the apps you need in the classroom or at work. Downloading apps individually, at a cost, can end up increasing the overall price of the device.

You may want to sell your graph calculator at some point down the road, especially if you purchased it for a particular class in high school or college. Be sure you consider the resale value of the choice you make now.

Texas Instrument calculators typically have a higher resale value than other brands. This is because the brand is popular among teachers, students and professionals, even though Casio models are generally less expensive and easier to use. In fact, some schools even require TI calculators for the classroom. The TI-84 Plus is the most popular when it comes to resale value because of its approval for use on standardized tests like the ACT and SAT.

**Warranty **

No matter what brand of graphing calculator you choose, see how long the warranty is. The majority come with a one-year limited manufacturer warranty. Be sure you understand what the warranty entails before purchase. Some only cover manufacturer defaults, while others are more comprehensive and cover everyday damage. Most calculators also feature durable exteriors and optional sliders and cases that help it withstand the daily abuse of being carried around and occasionally dropped. However, a warranty covers you if something goes wrong.

### Graphing Calculators: Our Verdict and Recommendations

When tackling algebraic, geometric or even statistical equations, the right graphing calculator makes a difference. Finding the ideal one for your needs depends on how you plan to use it. After looking over some of most popular on the market, our recommendations are:

**For Students **

The Texas Instruments Nspire CX includes almost all the features you want in a graph calculator for high school as well as many features that transfer well into college courses. While it doesn't have CAS capabilities, it uses mathematic templates that translate expressions into a textbook form that's easy to understand. It's also usable on most standardized tests and features a backlit color display that lets you easily see your calculations. The Casio PRIZM is also useful for students. It offers many of the same features as the TI-Nspire CX, and it is more user-friendly. However, it isn't as widely accepted or used in the classroom.

**For Teachers **

The TI-Nspire CX is also a good option for teachers. Using a calculator in the classroom that is compatible with many standardized and AP tests lets you teach students how the calculator works before these big exams. It also comes with rechargeable batteries, which help keep you going through every class period. Texas Instrument graphing calculators are ideal for teacher use in the classroom because this brand offers multiple teacher resources, like workshops, webinars and learning software. As a teacher, you may take advantage of the TI ViewPanels as well, which work with overhead projectors and let project your calculator screen so all your students have the ability to view what you are doing. Texas Instruments also offers EZ-spot yellow slide cases, which help you easily identify which calculators belong in the classroom and which belong to students.

**For Professionals **

While many advanced calculators are suitable for professionals, whether electrical engineers or professors, the HP 50g stands out with its CAS capabilities, along with its RPN and algebraic formatting options, massive equation library and large storage capacity. This option lets you do more than a traditional scientific calculator and makes finding the solutions to equations easy for professionals in astronomy, electrical engineering and physics.