I was on the fence between the TI89 and the HP Prime. After downloading the Prime app and the 89 emulator and going through a lot of videos on to use both I went with the 89 because it seems to do a few key things more easily (in my opinion) than the HP Prime. I needed it to dy/dx easily and factoring on a test is always nice to have. I also like that it takes AAA batteries. Always replace them and find when you need them. The HP Prime kind of scared me a bit because it has a rechargable, but the problem with that is that you never know if in 2 years (the apx life span of the battery) if you'll even be able to find it. If you do find it how much will it be? With how inflation is, it could cost 10,000$ who knows.Having the IT89 in hand it feels nice and it's a lot easier to do calculations when you're not clicking with a mouse on the emulator. So far so good. I expect this to be a good investment.

Está calculadora es de lo mejor con lo que debe de contar un ingeniero, estoy feliz de tener una de estas

Me parece muy completa en prácticamente todas las áreas de ingeniería , física y pienso que en química la recomiendo ampliamente

I bought the TI-89 Titanium to be compatible with a fellow engineer--it is great to be able to share code and math solutions for the same model of calculator. This is a switch for me, since I have always been a Hewlett-Packard fan. I have at least one of almost every model of HP graphing calculator, and many other models, going all the way back to 1972 and the HP 35. It never occurred to me that the TI-89 series could actually be competitive with HP. Well, it is! This calculator has some very nice features, and a few features that the similarly capable HP 49G does not. I'll leave it to the buyer to explore the manuals and figure some of that out for themselves. But I will definitely note that the Home screen edit/command line has superior behavior in several ways to the HP 49G. One of those is the retention of the last problem, equation or expression entered by the user. That means you can simply solve the first problem, then move the cursor around in the problem, replace a variable, change a sign, or make any other edit needed to evaluate the problem in different ways, without having to copy the equation/expression from the history (as you would have to do with the HP 49G).The HP 49G has more memory than the TI-89 Titanium (mine is a HW4 edition), and a more feature-rich file system (more like a PC). TI partially compensates for simpler filesystem by having apps show only files appropriate for the app you are using at the time, which helps avoid visual clutter. The TI-89 Titanium has a lot of useful, very high quality apps, preinstalled.Both models have a CAS and about 800 scientific functions, constants, and unit conversions but, while unit conversions are faster and easier on the HP 49G, unit math is better on the TI 89 Titanium if what you expect the calculator to do is simplify units to the most practical SI or SAE unit. As an example, if you multiply 200,000_Pa by 1_l, the simple answer is 200e3_Pa*l, but the most practical SI unit resulting from that product is the Joule. The TI-89 Titanium correctly substitutes units and answers with 200e3_J, while the HP 49G (and later RPL graphers) renders the easiest, but least helpful, answer of 200_kPa*l--the correct answer, but left in inconvenient units. (The 49G does have the advantage of having metric/engineering power-of-3 prefixes, such as k, M, G, m, n, etc.)In a way, the TI-89 series is as much a personal digital assistant (PDA) as it is a graphing calculator. This is the result of having numerous useful record-keeping applications, a clock/calendar, event scheduler, task manager, personal contact database, etc. The Titanium also comes preloaded with EE*Pro, a professional-quality problem solver app aimed primarily at electrical engineering professionals. The closest preloaded application HP shipped with a later model of the 49G series, the HP 50g, was a library of powerful equations copied from the HP 48G series, and an interactive Periodic Table of the Elements for chemistry. Don't get me wrong, those are very useful, and the Periodic Table app is better than ones I've seen for TI. But, the TI-89 series was marketed to students and professionals alike as more than just a graphing calculator with a CAS. It is a PDA. In 2020, that seems a silly point to make, given smartphones of today. But in 1999, when both the HP 49G and the TI-89 series were made, the TI appears to have been a better fit for students and, depending on the disciplines, maybe better for engineers. In most respects, the I prefer the HP, but some features of the TI are eye-opening ideas that explain to me why TI is still making graphing calculators for the US market today, while HP has fallen out of the business in the US, even after the release of the formidable and capable HP Prime (which is, in my opinion, superior to the TI-Nspire CX series). TI showed a better design balance with the 89 series, making the flagship graphing calculators fit either the student or the professional technical user, and most apps for the TI-89 series are of very high quality.One more point I will make, is that both are programmable; the TI-89 Titanium is natively programmable in TI BASIC, while the HP 49G is natively programmable in HP Basic and in UserRPL. HP Basic (not BASIC) is limited compared with TI's M68000 BASIC, but HP RPL is more powerful, more elegant, faster for most programs, and more efficient than TI's BASIC. However, TI BASIC is pretty intuitive, while RPL is considerably harder to learn if the user is not already familiar with Reverse Polish Notation and the HP stack or the Forth programming language (and its stack).Overall it is quite a toss up between the two. But if one were to ask me which brand to go with today, my answer would most probably be, "Go with TI. Get one of the TI-Nspire CX models if you are in high school or college and don't plan to use the calculator in a career, but get the TI-89 Titanium if you plan to keep using it beyond school and into your career." I am pleased with the design, speed, and ease of learning on the TI.

Sehr gutes Gerät; da ich das Vorgängermodell hatte, habe ich mich wieder für den TI-89 entschieden.Einziger Kritikpunkt die Produktbeschreibung stimmt mit dem Lieferumfang nicht ganz übereinLieferumfang lt Beschreibung auf amazon:4 AAA Batterien => checkUSB-Kabel für die USB-Schnittstelle => checkUSB-Kabel für die Verbindung zwischen TI-Rechner und Computer => checkHandbuch => leider neinProdukt CD der verfügbaren Software einschließlich der frei erhältlichen Applikationen und der Handbücher als PDF => checkEin physisches Handbuch aus Papier war leider nicht dabei. Desweiteren täuscht das Titelbild (was ich allerdings nicht negativ werte), da das Gerät selbst in einem Karton statt in einer Plastikverpackung kam.

Excellent. My son is using this for Calculus.

El producto llegó en excelentes condiciones y antes de la fecha planeada. Recomendaría el que compraran el producto por éste medio debido al precio y al servicio.

Ho acquistato questa calcolatrice per i miei studi universitari. Semplicemente perfetta, programmabile in tutto e per tutto e molto facile da usare. Certo all'inizio è un po difficile passare dalle classiche calcolatrici delle superiori a questa, ma una volta fatta pratica sarà essenziale per voi.Consigliata per studi universitari di matematica fisica ingegneria.