Casio FX-991EX Engineering/Scientific Calculator, Black (European Version), 3" x 6.5" x 0.4"

Lean, mean and not messing around; beware the new kid on the block! It annihilates the FX7400GII in terms of overall usefulness, yet can be had for two-thirds of the price (though this is beginning to creep up!). Appearance wise, Casio have broken with their traditional fx-83GT/fx-991ES shape and created something very different, with a clean, new look, that's almost a work of art. Its appearance is so good, I suspect it will sell just on those grounds alone! Put simply, it has real style; you almost feel in possession of a fashion accessory! Most photos don't do justice; hopefully my photo will! Although it isn't a graphical calculator as such, it has the capacity to draw graphs on your smart phone or tablet, via a scannable QP code and an app.They've improved the statistical functions so that in addition to the standardized, normal cumulative probaility distribution, you now also get the inverse cumulative normal distribution function, plus binomial and Poisson, probability and cumulative probability distributions. These are very useful to anyone doing S1 or S2 statistics modules for A-Level, and dispense with the need for tables of these functions. Most of this is absent on FX7400GII! What it offers, however, is still way short of the fx-9750GII, in this respect. You also get the ability to solve quadratic, cubic or quartic polynomial inequalities and the answer is given just as it should be written down, using the correct inequality symbols! Even the FX9860GII doesn't offer this at present! Other enhancements include better vector facilities: it now offers the ability to show you the angle between two vectors rather than leaving you to work it out via the dot-product. The FX7400GII has no vector facilities at all and doesn't even have a matrix mode! The FX9750GII does matrices but no vector mode! Only the next one up from that, the FX9860GII, does both, apart from the FX991ES, now available at roughly £16. For some, the cherry on the cake will be the addition of a basic spreadsheet mode (absent on the FX7400GII and the FX9750GII calculators). You also get an equation solving mode which is an enhanced version of the FX991ES. It now features a 'Solv' facility, designed to give approximate solutions, to many types of equation, as presented, using Newton's method. In this respect, however, the FX9750GII and FX9860GII are light years ahead with the 'SolveN' facility, as this often gives exact solutions (even as multiples of pi, where relevant on the fx-9860GII). You get a crystal clear, 'natural' display, with answers presented as surds, or multiples of pi, including fractions, where possible. FX7400GII can't do this and the FX9750GII only does it when uprated.The processor also seems faster than before. If there is a drawback, it has to be the fact that display history is cleared when the calculator is switched off and once you've performed a calculation, you can not go back, edit the history and recalculate, once the display shows ANS. Amazingly enough, evidence suggests that UK exam boards will allow it, despite no CAS features allowed. However mild, this calculator does have CAS features because it uses symbolic logic to write inequality regions. Fortunately, many teachers have taken to it and I suspect wires were be pulled by the more influential ones ('old boy' networks etc!) to get it approved for UK, GCE exams. Whether or not they'll achieve this for IB use, is another matter! Without an Exam Mode, similar to the FX9860GII or Graph 75/95, it would definitely be banned in France, for IB use, on account of the vector commands. It goes without saying, that now it's regarded as suitable for UK, GCE exam use, the FX991ES may now bite the dust or be offered at a lower price. This is something Casio could easily do because the circuit board is almost identical to the FX85GT-Plus, often available for under £10 and popular with GCSE students. In the past, however, Casio went to great lengths to prevent people getting too much of a bargain! Take the FX83ES as an example. It shared the same type of circuit board as the FX991ES and an HB pencil applied to the P4 jumper on it, would effectively turn it into one, from something no better than the current FX85GT Plus, within seconds. Yes!, you unleashed 5 extra modes and all the functions of FX991ES. Casio reacted by encapsulating the P4 jumper, to make it virtually impossible to do this any more. So, interesting times ahead and one does hope that models known and loved by students, here and abroad, like the FX9750GII will be around a bit longer. Ten years, however, is a long time in terms of technology and the FX9750GII first appeared in 2008! Does the FX991EX usher in the era of a new line up of scientific calculators? One wonders! In summary, there's a lot to like about Casio's new offering and one could say that at under £20, it redefines the market in the value-for-money stakes, providing many features hitherto not offered. On looks alone, it scores 10 out of 10. Its new keyboard layout, with extra keys such as OPTN (pity they didn't give it the EXIT key as well!) and main menu with attractive looking icons is also highly functional. It's slim, solar powered and has useful features not found on models costing three times the price. Here, I'm thinking of the polynomial inequality solver and the ratio solver. These will be an immediate hit with GCSE and A-Level students. Together with a basic spreadsheet facility in addition to other useful features which have been around for some time (eg matrices, vectors) and you really have an incredibly useful little machine! Some universities ban programmable calculators, so it's bound to have great appeal there! On the downside, don't expect the build quality of an fx-9860GII or even an fx-9750GII and do bear in mind that both these trounce it in terms of overall usefulness to the average A-Level student. Providing the fx-9750GII's OS is upgraded to the fx-9860GII, the extra facilities could be worth at least one extra grade in the exam! Savvy students good at IT would probably jump two grades! There are certain well-known, independent, private schools, which choose these models, for their students and in the US, a yellow school edition version of the fx-9750GII, is quite common. There may be school or college teachers out there thinking they should bulk buy the new fx991-ex. I'd urge caution! £50 will be affordable to most, and just on the basis of the 'SolveN' facility alone, justifies the extra cost of the fx-9750GII. With vastly superior statistical functions, bigger screen and the ability to graph functions, it really does win hands down. Both the fx-9750GII and the fx-9860GII are fully programmable, in a language almost identical to BASIC, with the full range of commands you'd expect. This could be a real aid in getting students interested in programming. With almost every mathematical and text symbol available, you can in effect write your own software to cover anything you consider important, but absent (within reason!). So, to maximize overall grades achieved, the fx-9750GII or fx-9860GII are still 'top dog' and this new offering must be seen as very much inferior. Let me end on another negative point! Whilst the price of the fx-9750GII has come down from £65 to £49.99, in the last couple of months, the price of this one has risen (to as much as £32.50, here on Amazon). At under £20, it's stellar value for anyone wanting to cut costs. At £27, however, it's starting to look expensive. Anything more than £30, and it falls into the 'betwixt and between' category. The average GCE student should pay the extra £18 and go for the fx-9750GII. The cheapskate, however, would be better off with the fx-991ES Plus, readily available at £18 (currently about £16 on Amazon) and still a great little calculator or the Canon F-789SGA (better made than the fx991es, with slightly more functions and selling for roughly £18). WHAT SEEMS RIDICULOUS IS THAT FROM AMAZON.COM, THE UK PURCHASER CAN GET IT FOR £18.50! IN OTHER WORDS YET AGAIN, THE UK CONSUMER GETS RIPPED OFF! DON'T HAVE IT!! Let's also be quite clear that despite its good looks and superb blend of features, the fx-991EX is really just a tweaked version of its predecessor. It's not programmable, isn't a true graphical calculator, can't connect to your PC and can't take additional apps, like an fx-9860GII or uprated fx-9750GII. In short: a great little calculator but most GCE students would be far better off paying the extra for the fx-9750GII.

All my students love this calculator. They love the new look and they especially like the easier to use functionality.This calculator does not do much more than the 991-ES bu the smaller high resolution graphics make the calculations easier to see and understand. The new menu system is much easier to follow and although it does not do more than the previous version, it seems like it can. Most of my students using this calculator found and started using functions and equation which were easier to find and thus more usable. This makes simultaneous equations and solving quadratics a breeze. Both my A level and GCSE students have started to enjoy some of the calculator questions more. They want to use the calculator. The STO store and RCL recall buttons have been swapped and this has made something which all my students found difficult and not obvious with Casio calculators much easier. Now the students can save and recall memories without being taught this. This calculator takes a few moments getting use to - to use the menus to do everything but after that it is really popular and no one wants to use the old fx-85GT Plus or fx-991ES Plus calculators at all. Positives The look - everyone comments on the embossed modern look. The improved buttons - these look like that the ink will not rub off as in the previous models The Navigation Screens The four way button rather than the rocking button New colours The easy of functionality using the Option button rather than looking for the button on the keyboard Negatives Having to search the students at the end of the lessons. They all want one now!

As a little bit of a calculator nerd, I've used many different calculators over the years. When it comes to scientific calculators there is a vast range to choose from, Casio being at the forefront of those avaliable and often the go to calculators for many students. However, as time progresses even with experience in using the relatively simple Casio-style scientific calculators, according the more complex functions can be a little bewildering. I heard about the FX-911EX approximately a year ago when they were first released in Japan and extremely hard to get hold of. I was amazed by their high resolution display to allows the calculator to display full text rather than abbreviations. For example, say goodbye to the constant or conversion codes on the lid as all the information may be read from the display. A year later they have become more avaliable, albeit more expensive than if you import them. But trust me, the cost for ease of use is a blessing and so don't be deterred. It also has far more advanced functions, which I would normally only expect to find on my Casio FX-CG20 Graphical calculator, such as Distributions. I've never looked back at any other scientific calculator, and I would highly recommend it to anyone taking a GCSE, A-Level or Higher Education. Some of my colleagues having used my calculator have even gone out and bought their own - it's just a frankly awesome calculator!

As an A-level maths teacher, these have become the de facto calculator for A-level use. There aren’t a lot of other options on the market as, in the new specification, you need to have a calculator which holds the Binomial Probability and Cumulative Distribution Values. The menus are a bit clumsy, and don’t remember values as you swap between them. There are some really useful functions which can save time in an exam - it is worth knowing your calculator as well as you know your mobile phone and it will be really valuable in an exam.

This Casio fx-991EX gives everything a GCSE / A Level maths student needs to enhance the chances of passing the exam with better grades. You can factorise quadratic functions, solve simultaneous equations, solve linear equations, Table feature helps you to plot graphs, You can figure out ratios. You can solve quadratic inequalities. You can do unit conversion and work out prime factors . You can evaluate mean and standard deviations and all other associated statistical parameters. From data you can work out PMCC and regression coefficients. Not to mention all the stats tables inside the calculator for you to work out binomial and normal probabilities. For Further Maths students it helps you with matrices and vector calculations too. I did not mention any basic features as it is taken for granted. In my opinion, every GCSE and A level student must have this calculator Casio fx-991EX

A worthy successor to the Casio fx-991ES PLUS. This is pretty much the best calculator you can get until you reach the point where you need a graphing calculator, which right now means A Level. Anything below - GCSE, Year 9/8/7/etc. - and this is an ideal calculator. As an aside, even at A Level, this makes a great scientific calculator as a companion to a graphing calculator; it's best to take a scientific and graphing calculator into A Level exams. Other improvements over the fx-991 series: * The internals have also been upgraded, so certain operations (e.g. numerical integration) are MUCH quicker. * The look of the calculator is much cleaner * The screen is much higher definition, greatly helping legibility * The menus are now graphical instead of abbreviated * The calculator tells you when you're on solar and when you're draining the battery * Much simpler reset procedure for exams All in all, an excellent calculator - and the fact that it's dual solar/battery powered is a nice bonus.

Bought this calculator for my 16 year old who is soon to start her A level maths and intends to go on to uni (hopefully). The calculator is well made sturdy with easy to use keys and excellent functions. the graphics in the display are clear and of good definition. This calculator is recommended for maths, further maths and sciences, will see her through uni (hopefully). I WOULD DEFINATELY RECOMMEND.

My son needed this calculator for A level Maths, this is the calculator that was recommended by his teachers, it is quite easy to use, its not a graphic calculator but great to be use with a graphic calculator. Really good for solving quadratic equations and my son says it is easy to use, not the cheapest calculator especially if like me you have already bought a graphic calculator as well but this is the main calculator my son uses!

Lots of functionality and easy to use. The combination of battery and solar is welcome as well. Great for kids and adults.

I saw a review saying that it's not genuine so I was a little worried. But don't worry, I can assure you that it was 100% genuine, I did the authenticity checks with the QR code generation and checking the battery compartment. This costs the same as the fx-97SG you can get at Popular but with way more functions! You have logarithms with customisable bases, stored numerical constants, a series generator, differential and integral calculator, prime factor decomposition, solving for x and many more. If you are an engineering student this is the perfect calculator for you. It will save your butt during your exams because you can directly obtain your answer from the calculator so you'll be able to spot any careless mistakes in your working.

Great scientific cal

Perfect for engineering tasks

Não é uma calculadora barata, mas investi nela por recomendações de professores e de outros alunos e não tenho arrependimentos, de fato foi uma compra que valeu a pena e recomendo para cursos de engenharia ou outro na área de exatas. Comprei ela em março/abril de 2022 e estou avaliando em novembro de 2022, até hoje nunca apresentou defeitos ou falhas perceptíveis, veio bem embalada e em ótimo funcionamento. Acredito que vá durar bastante e será minha fiel aliada nessa caminhada