Texas Instruments TI-89 Advanced Graphing Calculator
by Texas Instruments
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Our Price: $249.25 Availability: Usually ships in 1-2 business days Buy Used: from $68.15 (click here) Category: CE See more product details |
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Digital Cameras Photo Reviews of Texas Instruments TI-89 Advanced Graphing Calculator
Customer Review: Does alot of advanced things, but lacks alot
Summary: 4 Stars
The calculator is just simply amazing, it has a calculus menu with many functions (integration, differentiation, sums, limits, etc), its algebra menu factors, expands, and solves; and these are easily accesible with the F2/3 keys. One of the best things about it however is its CAS (Computer Algebra System) which leaves things in exact format (in radical form, pi, e, etc) and ability to work with variables, its numerical solver (ex. just put |x=(3/7) after the equation to put in its x value and it will replace all x's with (3/7)) also saves alot of time. Its pretty print is also great, it writes things just like how you would in your text book (integral symbols, fractions, exponents, radicals, etc), making finding mistakes easy. Some of the downsides of the product however is it "renaming" trig functions like sec csc cot to cosh, sinh, tanh(and it doesnt even leave that in simplist trig form (reciprocal identities), that is, 1/cos(x) does not equal sec(x) or cosh(x) but it considers 1/cos(x) in simplist form), it also cannot calculate some simple trig limits like lim x->0 cos(x)/x and its log button is also a major pain to get. It also lacks a xroot button, you have to use the exponent key for roots higher than squares. Also when tracing or anything involving the keypad it takes a few seconds for it to be "held" down, unlike the TI-83 and 85 where when you hold it down its instantaneous. The programs you can download for it are great, but you have buy the TI-Graph Link and the programs themselves are also in most cases cumbersome to use (shift -, hold down cursor (which is a pain because of the above) then select, and close bracket). You also have to pay for some programs, like Cabri-Geometry just to download it from TI - $30.
With all things considered this calculator is great, and I would recommend it IF you have another calculator, because its a pain to do some things, I carry around my TI-83+ with me also to do simple stuff. ALSO! If you decide to buy this CHECK WITH YOUR SCHOOL/COLLEGE FIRST! Some schools/profs do not allow it because of its CAS, you also cannot use it on some college entrance exams.
Customer Review: Considerations before buying the TI-89
Summary: 4 Stars
Other reviewers have discussed the pros and cons of this calculator's features. In this review I will discuss more practical considerations that argue for a less powerful calculator for classwork.First, despite the fact that this calculator is acceptable for use on various college admissions tests (e.g., certain SAT II and AP exams), it may be banned for coursework (at least during tests). For example, the symbolic math capabilities may make the calculator too powerful for calculus and other math classes (for example, I cannot use my TI-89 in my linear algebra class). A TI-83 or TI-86 would generally not be considered too powerful.
Second, the varieties of the TI-83 seem to be the current classroom standard. Teachers tend to know this calculator and may demonstrate how to solve problems with the TI-83. You may be permitted to use a different calculator, but you may be on your own.
Third, while the TI-89 may be more powerful, various functions are harder to access than on a TI-83. For example, if you need to compute a common logarithm, it's a single keystroke on the TI-83 but only available through a menu on the TI-89. Similarly, the TI-83 has a single key to get to matrix functions, but for the TI-89 you enter a matrix using an application from the APPS key, and matrix operations are accessed through the MATH/Matrix menus.
Fourth, the TI-83 displays larger characters on the screen than the TI-89. This generally makes the TI-83 easier to read (but sometimes being able to fit more information on the screen improves readability).
The TI-89 is arguably a more powerful calculator than the TI-83 or TI-86. Consider whether that extra power is worth the extra cost, both monetary and other as described in this review. You may find the TI-83 provides all the functionality you need at a lower cost.
My rating of four stars is for those people who need its power. I do not rate it a five-star product because it is not as usable as it could be (there is a fixed, relatively small size for the displayed characters, and some common functions such as log should be easier to access).
Customer Review: A Calculator for the Serious Mathematician
Summary: 5 Stars
Check with your instructors if you plan to buy this calculator for use in math if you only wish to fill your degree requirement. Many instructors are aware of the power of this calculator and may not allow you to use it on tests. (This calculator is a portable answer key to anyone who knows how to use it.) If you plan to fill your math requirements and move on, maybe the Ti-83 may be better suited because it is cheaper yet still a good graphing calculator.If you are in need of a portable math computer, or even portable math tutor this may be for you. It takes time to figure it out. The manual that comes with is a book, but it is an abridged version of the full manual, which is 600 pages. Once you get the hang of it (this could take days, weeks, or months), you may find that the format is so consistent that you don't need to consult the manual to learn new functions.
I have a second calculator to use on my calculus exams because this particular calculator is not allowed, but I find this to be a great answer key to even problems. I also use the algebra functions to break down calculus problems if I have trouble finding the answer on my own. To me the Ti-89 has saved itself its cost in solutions manuals - this is me and may not fit your study needs.
Since I keep 2 calculators, this one and a lesser calculator for may tests; I can see a vast difference. The Ti-89 is built mechanically as well as it is electronically. The display and format are very crisp and easy to use. Both my calculators get knocked around. My cheepy is dented a bit, but the Ti-89 is still like new. I've had this calculator for 8 months with continual use and the buttons are not even worn. If you use this calculator enough you may find yourself automatically using both your hands at once - this calculator is so fast and easy to use once you get the hang of it. The display gives an instant verification of your entry in a beautiful,easy-to-read format.
Customer Review: Take it from an Engineering Student
Summary: 5 Stars
As a Computer Engineering student, this calculator has been as invaluable to me as MatLab has been on the PC. Indefinite integrals, pretty print, all the beautiful units cancelling out for you when you're not sure you remember that formula... who could ask for anything more? It's basically a TI-92 with some more features in some ways and less in others, but for you high schoolers: It's accepted on standardized tests! This is when I first fell in love with it, when I took it into my AP Calculus BC exam 2 years ago and it saved my bacon. Don't get me wrong, it's important to know all your calculus, but when you're solving a differential equation with complex roots for the characteristic equation, the last thing you want to be doing is actually having to worry about manually finding out what those roots are. This calculator is the one that in high school will cause you to skip the studying and rely on it to get you through a test. In college, for any major with hard-hitting calculus requirements, it'll be the calculator that does the dirty work for you so you can get to doing the stuff a calculator just can't do. Where other calculators stop (precalculus levels and definite integrals), this calculator keeps proving itself through differential equations and multivariable calculus. It's beautiful to be able to see for yourself what that three dimensional shape you're working on actually looks like, instead of having to rely on (at least my) awful drawing skills. Trust me, this is the "killer-app" of calculators. It's probably not even worth splurging on the TI-92 if you have the cash... it might play some cooler games and all, but I use my TI-85 for games... because that's all it's good for when my TI-89 is powered up and ready to go in my pack.Customer Review: DO NOT BUY ANY OTHER CALCULATOR
Summary: 5 Stars
This is the ultimate calculator (at least up to this point in time). Probably the nicest thing about the 89 is the ability to display the functions and eqations in the same format as they would appear written on paper. Additionally it, whenever possible, will give an exact answer in terms of mathematical constants like pi, e, and i, instead of the decimal approximation. For large answers like 75^76 the calculator has the ability to print out an exact answer up to several hundered places without having to resort to scientific notation. Add to these features such unheard of things for calculators as symbolic integration, taylor series expantion, a text editor (for scanning in the pages form your text book into), and even symbolic simultaneous equation solving. About the only thing i was really disapointed in with this calculator is the inability to solve functions such as ln(-1) which should be Pi*i. It was possible to compute this with earlier TI calculators. I cant see why they would take out that feature. But so much is built into this calculator that I actually learned some stuff from it. For instance it is possible to take the factorial of a number like Pi even though it is not an interger. Some other features of this wonderful calculator include 3d graphing, an unbeatable selection of games (including zelda and super mario brothers), built in assembly programming, a complete library of physical units and constants, and copy and paste features. I have owned the TI-85, TI-86 and now i have the TI-89. I make fun of all my friends who have the TI-83 because it looks like an abacas next to the 89. Trust me, this is the best calculator out there. It got me a 5 on the AP Calc and Physics Tests.