Texas Instruments TI-89 Titanium Graphing Calculator
by Texas Instruments
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Digital Cameras Photo Reviews of Texas Instruments TI-89 Titanium Graphing Calculator
Customer Review: Very good quality machine with good improvements over the TI-89
Summary: 4 Stars
I have owned top of the line graphing and scientific calculators from TI, HP, Casio, Sharp, etc. Back when I was a student, TI's were very cheaply made and often broke quite easily. This machine, the TI-89, Titanium, is definitely not cheaply made and is definitely put together very well. It is also a good improvement over its predecessor, the TI-89 with more memory and with an improved keyboard and improved keyboard "feel" and a much better feature set, etc. The pros and cons as I see it are:
PROS:
1) It has all the standard and CAS (Computer Algebra SYstem) features that we have come to expect on such a machine, plus many nice very detailed and topic as well as course specific APPS that are already preloaded or can be added in electronically and quite simply from the TI website. The interface with a computer is fast and easy to set up.
2) It has a very nice calendar and note storage system for keeping track of coursework and daily workload assignments.
3) It is quite fast with a nice graphical interface and resultant plotting system. The resultant plots are high quality and with the many added features available for enhancement are very intuitive for the learning process.
4) The icon system for choosing where you want to be on the machine can also be converted to a much easier and quicker to navigate text-list system.
5) It has a nice and quite modern, curved body design that sits very nicely both on a desk or a table as well as in your hand.
6) It has a large amount of onboard main memory, plus additional Flash memory for tackling quite memory intensive problems.
CONS:
1) There is no SD card slot as on the HP50g.
2) Integrals are completed by a table look-up process and not by direct manipulation so very little insight can be found by students as to why the result appears the way it does. On the HP50g, in step by step mode, much insight can be gained by the manner in which the integrals are performed for example.
3) The algebraic operating system is the only choice available on this machine which usually requires many more keystrokes to do a complicated problem.
4) The available programming languages are quite limited on this machine as compared again to the HP50g.
5) Some functions that you would readily expect to be available with a single key press require instead at least two key presses, but usually with only a single shift key press first.
6) The color coding choices are not nearly as distinctive and easy to quickly recognize as on the HP50g.
7) As with the HP50g, it require multiple batteries plus a backup coin cell battery to save everything briefly when changing the main batteries.
8) TI should also impliment a fine backlight system for viewing the screen at low light levels, as recently included on the Casio FX-9860g Slim version for example.
Customer Review: Terrible UI: not for serious users; the entry line is far too small for complex equations.
Summary: 1 Stars
The user interface on this calculator is terrible. Tabs on the top of the screen that you can't get rid of taking up a whole 15% of the vertical display (especially considering how small it is)? They should just use a button that drops down the tab bar when needed. This would free up a sizable portion of the screen that otherwise goes to waste if you don't need any of the functions listed in this tab bar at the top of the screen (which many users don't half the time).
But my main problem with this calculator is how utterly useless it is for writing equations larger than about 2 calculator screen widths (depending on how great your visual and spacial memory is). The equation entry line that you type into is only one line high and thus, when you're writing large equations (particularly anything with imaginary numbers as this tends to double the equation size), you often are using two and three screen widths for the equations. I find half of the time I spend using this calculator is spent scrolling back and forth making parenthesis adjustments. There's two speeds for scrolling left and right: all the way, or about 8 characters/second. Seeing as the text entry line is 25 characters long, when you're talking about editing 75 character equations you can easily spend 5 or 6 seconds navigating to a single section of the equation to make a change. If you need to make three or four adjustments editing a single equation easily takes 20 seconds when it should take half that. If this calculator had a "jump 6 characters left/right" it would make all the difference in the world. As it stands, this calculator is much more frustrating to use than my 83+. I would still use it if it could handle the kind of equations one turns to this sort of calculator for in the first place.
I will be looking around for a substitute calculator and update in the future when I find one, but rest assured if you're building any complex equations you MUST write down the full equation on paper first with parenthesis or you will probably input it wrong like and spend 45 seconds scrolling back and forth trying to figure out which of the 7 nested parenthesis you've made a mistake in. Even then, if you have to go back and change the numbers or add a value you'll still be wasting valuable [test?] time scrolling back and forth. At any rate, you shouldn't be limited to writing down the equation first on paper before solving; on an 83+ you can build the whole equation right there and quickly make any adjustments, but alas the 83+/86 can't do these complex integrals.
Yes, this calculator can integrate for you and do all sorts of wonderful graphs and integrations, but the kind of integrations you need a calculator for are NOT one line equations! You can do S(x^2) in your head; but it seems this kind of equation is chiefly what the calculator was designed for. I highly recommend looking elsewhere.
I hope this review has helped you make the right decision.
Customer Review: Does alot but not everything.
Summary: 5 Stars
Preface: I'm very close to graduating from college, in engineering, so I've used this calculator for high school calc, calc 2, vector calc, chemistry, various engr. courses, probability classes, etc etc. This calculator doesn't have a learning curve per say. Everything is actually quite intuitive to use unlike HP's calcs which require a dozen button presses just to add two numbers. However, the difficulty in usage comes from the fact that you often won't know this calculator *can* do something you have to do. For example, did you know that if you hit the diamond key and then 7, that you'll get a log() without having to use the catalog? (diamond 7, diamond 9, and diamond | are the most useful hidden commands) I would suggest buying this calculator a few months before you actually need it, and spend some time playing around with it and figuring it out.
Yes this calculator is extremely reliable and extremely useful, but I find a lot of the time it's actually overkill (beyond Algebra I never have had to use the graphing functionality which is pretty limited (low res) anyways). The functions I've mainly used over the last 5 years are solve() (use this alot), nPr, nCr, >Polar, >Rectangular, complex number stuff, and expand(). Integration and differentiation are only really useful in calc 1 and some of calc 2, but beyond that the integrations are too complex for this calc to handle and you have to do them by hand. In a lot of other cases this calculator will be able to do something but will spit out the result in a weird format, requiring you to double check it by hand.
A lot of the power lies in being able to install applications to this calculator (some written by TI, some not) and being able to write your own functions. For example, simultaneous equation solver is extremely useful for linear algebra. I've also written various functions to perform operations that would otherwise require multiple steps or mile-long equations (for example, the electron drift velocity of a semiconductor), which is very useful. The program editor on this calculator is fairly intuitive once you get the hang of it by seeing some examples.
And you can obviously also use this calculator along with TI's Notefolio to cheat by storing equations and the like. It's far from a holy grail though especially since you only have a 26x9 character window to work with but it can be a lifesaver in certain classes where you otherwise cram-memorize-forget the day after.
I would recommend this calculator over a TI-84 or -83 simply because the interface and text display are geared more for an adult whereas the -83 is more useful for basic arithmetic and graphing (algebra I and below). The -83 also lacks a lot of applications which are only available for the -89. In summary this calculator is a tool that does well reducing busy-work that you might come across, but it is far from being a second brain.
Customer Review: Ti-89 84 Silver or other?
Summary: 4 Stars
Hi there.
I owned both Ti89 and Ti84 Silver so I am trying to comment about these 2 as fair as possible.
Ti-84 is pretty good I believe. You can plot data tables and find best-fit curves, lines... to predict the trend. Further more, the built-in SOLVE is very powerful, it solve almost any equations. But the cons is it only give u one solution at a time and require you to guess. It is kinda annoying because sometime, there are more than one solutions and you have no idea how to guess. I think Ti designers force student to guess so that (they think) we will learn to guess reasonably, not just to obtain the answers. Beside, you have a whole bunch of financial functions which I have never used, let business majors people play with it. The best thing about the Ti84 is its graphing ability. You can find max, min, x-intercept, intersect (2 curves), graph 3D (third party apps).
So if you prefer numerical solving calculator, Ti-84 is a monster.
About the Ti-89:
It is a big WOW to me. In fact, I would say that the 89 offers you better bang for your bucks, just more expensive but much much much more functions than the 84. In fact, it can solve almost all problems in my Math books... However, the best thing about its solving capability is also the worst thing to students. Guess what? You go to school and let this monster "study" for you and you graduate with an empty head. Therefore, it is definitely not a best choice for students. I am a bit sorry that I have purchased the 89 right now. It is always up to you to choose. The 84 is very good choice for students and on the other hand, 89 is harmful to students. In my opinion, the Ti89 is somewhat in between of Computer Math software and a normal graphing Calculator such as the 84. And please keep this in mind: You probably aren't allowed to use the 89 during exams.
I also have heard many good feedback about the Casio graphers too. People said they beat all Ti model from 84 because they are not only cheaper but better design and functionalities than Ti84. Honestly, I don't have Casio graphing Calculator but I have Casio Scientific Calculator since I was in high school. I believe, Ti scientific calc can't compare with those Casio ones. They rocks!!! And I don't work for Ti or Casio.
Conclusion:
I believe for students (Math students) the Ti-84 or a graphing Casio is an excellent choice.
How about advanced Math? Use computer software instead. The 89 extends its solving capabilities closer to computers yet still not there yet.
So A Casio grapher (half price the Ti) and a Math software such as Maple or Maxima (Freeware)... you have optimize your investment.
Customer Review: Found my mistress!
Summary: 5 Stars
From slide rulers to Ti-89's, let me tell you! Even my proessor wanted to use it! Long story short, I have never owned a graphing calculator until now. I am auditing a calculus class this summer and needed something more powerful than my Casio fx-115ES (which is sweet, BTW). My Casio can integrate, but not do diff Q's.
Well, let me start by price. My friends all suggested I bought and used a Ti-86 or even a Ti-85 unless I was going into a technical major. Surprise, surprise, I'm an engineer major. I figured if I was going to shell out over $100 on a calculator, I should choose the best available. Needless to say, everyone knew about the Ti-89. I showed it to my math professor who had the same reaction as me (think a kid on Christmas morning opening his gifts). The first thing he asked was "How much was it?" I told him I paid $140 clams and he said "Wow! How'd you get it so cheap?" It wasn't just him though. I showed my buddy in AutoCAD and he was astonished by the price as well.
Next is features. I loved the fact that it came with an instruction booklet and the batteries. It let me jump into playing with it the minute I got it. The book is about the size of a video game manual (assuming a modern-day RPG). There is a lot to read and I am still reading it. It's not too hard to figure some things out assuming you're rather savvy with electronics and have some free time on your hands. I learned to graph polynomial functions while walking to class! Italready has pre-loaded apps, but I will ask around and get some more when I finally have a chance (and some sleep), since several apps are useful for certain classes.
Next is size. I know graphing calculators are big, but wow! It doesn't fit in my pockets, that's for sure! I usually stick it in my backpack or in my cargo pockets on days when I have those kinds of pants.
Finally, utility. As I am still using it and figuring it out, it seems to do basically anything I need it to do. I am contemplating buying the Dummies' book for it since that might tell me something the instruction booklet omits, plus they often have tips within!
Overall, I would say it is a must-buy. Most of my friends (90% engineer majors) have older models and would kill for a Ti-89. It is a steal at some prices and I love the fact that even my math professor was impressed and asked me if I could bring it by his office sometime. I love calculators and this seems to be the best out there. If you don't want to break the bank, but want something good, try the aforementioned calculator (Casio) since it worked great for me!