Casio FX991EX Scientific Calculator 192x63

Performance:FairQuality:Not sure about its authenticity. There are no any qr code to check it. Neither in the box nor in the calculator.Suitability:FairHow to check Authenticity:1. Scan QR CODE in the box, leading to Casio website and will verify if the calculator is authentic or not.Or can also try different way...2. Press "ON", and then "MENU", then "SHIFT", then "OPTN". A QR CODE will appear for you to scan it for authentication purposes.

Casio FX-991EX Review

First of all if you have anyone who is and/or just started secondary school I would seriously encourage anyone to purchase this calculator. Although it say's GCSE or A Level for a scientific calculator this is standard and recognized for all secondary school maths and further education. You won't need to purchase the more expensive graphics calculator as this one has so many features it's a lot more cheaper and offers best value for money amongst all the other models and other makes. WORD OF WARNING... Beware of counterfeit models which look exactly the same as the original in fact you cannot tell the difference part from the following. 1. If you place your hand over the solar panel window you should see in icon which looks like a sun disappear and/or the display ... MoreFirst of all if you have anyone who is and/or just started secondary school I would seriously encourage anyone to purchase this calculator. Although it say's GCSE or A Level for a scientific calculator this is standard and recognized for all secondary school maths and further education. You won't need to purchase the more expensive graphics calculator as this one has so many features it's a lot more cheaper and offers best value for money amongst all the other models and other makes. WORD OF WARNING... Beware of counterfeit models which look exactly the same as the original in fact you cannot tell the difference part from the following. 1. If you place your hand over the solar panel window you should see in icon which looks like a sun disappear and/or the display dim slightly. 2. This calculator is solar powered but has a battery backup as well, if you open the battery compartment there should be a battery inside. 3. There's a Casio App you can install on your Apple or Android phone, this calculator has a unique feature that after any computation it can generate a QR code and you scan this with your phone using the App. This will then open a webpage on your device and show the math equation. This feature isn't a necessary requirement for day to day use but it will confirm ifyou have a genuine product or not. All-in-All this is a brilliant product not just for students but for anyone just to have on their desk, workshop and/or at home. Hope this Helps :-)

Casio fx991 EX calculator for A level Maths

If you are studying A level in the UK, this is a calculator every student must have. It solves quadratic, cubic equations, you can solve simultaneous equations, check your integration and differentiation answers. You can calculation mean and standard deviation. You dont need statistical tables anymore, this calculator will give me Binomial, Poisson and Normal distribution probabilities. Does matrices and vectors too for the Further maths students?

Fake Casio and some of the mathematical functions give incorrect results!

I ordered this for my daughter to use in her maths A level which requires the Casio FX991EX. It worked for most calculations and she used it in her mathematical mechanics exam and all seemed fine but today she got stuck on various stats questions for paper 2, not managing to solve the questions, so she went through them with her teacher and it turned out that the calculator was giving the WRONG results on certain functions! They then looked more closely at the calculator and compared it to the teacher's one, which was giving correct answers - and realised it is a fake Casio! This could have cost her her A level.

The Ultimate Compromise

It trumps everything on the market in the value-for-money stakes, offering a viable alternative to expensive, graphical-plot calculators, at an unbelievably low price. What Casio did was incredible: they addressed the needs of those wanting a much more expensive, high-end, graphical-plot calculator, like the fx-cg50, but couldn't afford one. What you get here is all the features you'd look for in a more expensive calculator allowed for GCE use, but in a much slimmer body, less than half the price, and with a few extra facilities high-end models don't offer. As an example, it can solve polynomial inequalities, giving you the answer as it should be written down (even the fx-cg50 can't do this). Apart form it's ability to solve single-variable equations, as presented ... MoreIt trumps everything on the market in the value-for-money stakes, offering a viable alternative to expensive, graphical-plot calculators, at an unbelievably low price. What Casio did was incredible: they addressed the needs of those wanting a much more expensive, high-end, graphical-plot calculator, like the fx-cg50, but couldn't afford one. What you get here is all the features you'd look for in a more expensive calculator allowed for GCE use, but in a much slimmer body, less than half the price, and with a few extra facilities high-end models don't offer. As an example, it can solve polynomial inequalities, giving you the answer as it should be written down (even the fx-cg50 can't do this). Apart form it's ability to solve single-variable equations, as presented with no rearrangement, it also has matrix, vector, statistical distribution facilities, dual tables, spreadsheets, and an equation-solving mode for simultaneous equations with up to 4 unknowns, and polynomial equations up to powers of 4. You also get a ratio solver; HCF, LCM and prime factorisation. It's dual powered, and even outputs data for graphical plotting via an app on your smartphone. Good quality? Only time will tell, but Casio have over 45 years of experience, and offer a 3-year warranty, so it should provereliable, even if the keyboard does feels a bit trashy.

Too fancy-schmancy for everyday use

One of the keys on my trusty old fx-260 had become erratic (it's over 20 years old, so I can't complain) and I decided to upgrade to the state-of-the-art fx-991ex. Unfortunately, I don't like it. First, my minor gripes: (1) It's too big; I love the pocketable size of the fx-260; (2) the keys feel like chiclets and make a rattling sound when pressed; (3) the mottled surface texture makes the alternate key labels hard to read, especially the blue ones - practically impossible except in very bright light - what were they thinking? (4) The slide-on cover is too loose-fitting, slips off by itself. But more importantly, (5) I find that I don't like its main attraction, the V.P.A.M. entry method. The display is pretty and I like how the entered formula remains on display ... MoreOne of the keys on my trusty old fx-260 had become erratic (it's over 20 years old, so I can't complain) and I decided to upgrade to the state-of-the-art fx-991ex. Unfortunately, I don't like it. First, my minor gripes: (1) It's too big; I love the pocketable size of the fx-260; (2) the keys feel like chiclets and make a rattling sound when pressed; (3) the mottled surface texture makes the alternate key labels hard to read, especially the blue ones - practically impossible except in very bright light - what were they thinking? (4) The slide-on cover is too loose-fitting, slips off by itself. But more importantly, (5) I find that I don't like its main attraction, the V.P.A.M. entry method. The display is pretty and I like how the entered formula remains on display together with the answer - but it's cumbersome: expressions used in everyday math and science require more clicks than with the "immediate entry" method. And the whole menu system - who uses a calculator for spreadsheets or matrix calculations? Come on. -- The fx-991ex is a very cool calculator and I'm keeping it to show off to family and friends, but I got myself a replacement fx-260 for everyday use. (Secretely, I want a SwissMicro dm42, but they're just too expensive.)