CASIO FX-991EX Advanced Scientific Calculator (UK Version) &Oxford Helix Maths Set with Storage Tin

Note: This is not your typical scientific calculator; it's an upgraded version with many new additional features.In comparison to the typical one, this one can do some of the following:* Find the area under the curve of most graphs (integration)* Find the gradient at any specific point you want (differentiation)* Solve equations including polynomials up to an n value of 4* Matrices* Vectors* Distributions* Etc....I can say this because I actually have your standard scientific calculator and this one. This is why it may come across more expensive so don't buy if you don't need - generally this is a calculator that you would use in university or A-Level maths; anything else, just buy the original one.I hope this was helpful!

I realise most people using scientific calculators will be young people with healthy eyes but beware if you are older or have bad eyesight. I have cataracts and glaucoma and this calculator is the worst calculator I have seen for being easy to see.First the display: On older calculators like the 991MS the display uses that older type of LCD display where numbers are made up of 7 solid segements. These were a lot easy to read. Modern casios use what is basically an lcd pixel display but monochrome. In calculators like the 85gtplus it was not so bad but in newer calcs like the 85gtx and this 911ex the numbers are even smaller and harder to see.Then there is the background underneath the button labels. On past calculators it was plain; on more modern ones like this 991ex and the 85gtx it is a textured background which makes it harder to read the button labels.Lastly there is the fact that the top row of buttons on the 991ex including the cursors are made of reflective silver and catch the light like nobody's business. If you have cataracts like me it's like facing a 1970s cylon every time you go to use the calculator.The actual calculator is great and has all the functions I wanted and more and is a very reasonable price. I just wish they made it easier on the eyes.edit: Actually I'm a bit disappointed that the prime factorization function doesn't handle larger numbers. I expect it to have limits but it won't even do Jevons' Number (8616460799).

Outside of a graphing calculator, which is a much more expensive and complex proposition, this has to be the best you can get. Casio has spent years refining the way these things work, and it shows. The keyboard, for instance, is faultless. The display, considering it's not backlit, is very clear, and higher resolution than in previous models so you can have more rows in a table or spreadsheet. It's a very fast calculator too, with most operations happening instantly. Mostly it works on solar power, and there's a little 'sun' icon to tell you this is happening. If the light's too dim, the LR44 backup battery will take over, and since this is just about the most widely available button cell battery, you should be able to replace it easily and for peanuts.The range of functions on offer is amazing – almost too much until you get your head around them. Might be worth watching some YouTube videos for this. There are quite a few on this calculator and others that work like it does. One cool feature is the 'QR code' creator that puts a QR code on the screen you can scan with your phone to get graphical representations of functions through the Casio app that you would be able to put into projects. Nice.If you're tempted to get a cheaper brand to save a couple of quid, don't bother. This is such a low price you may as well have the best. You won't get the great keyboard with a cheaper brand, or the speed, or the cool carbon-fibre effect body. Casios are always well built and last forever. This one weighs nothing but feels good and well built although the hard case it fits into is a little bit rattly and being white will show dirt.My only other criticisms are that some of the text on the keyboard is a bit too small to read comfortably, especially on the textured surface, and the same thing applies to some of the text on the screen too, like the list of scientific constants. And this comes in a blister pack that you have to destroy to open instead of a simple box you can keep. Small beer.Really, this is about as good as it gets. It's outstanding. Just get one.

Extremely powerful in terms of features and usable within a GCSE exam setting. My son is impressed with it (not that he's excited by calculators!) and we've now bought another for our daughter.

Good buttons in terms of feel, legibility, and that they don't wiggle around in their housing. The printing on the face of the calculator is also clear. Great functionality.However, the screen font is dreadful, a sort of Times New Roman Affair that is hard to read generally and particularly when viewing from an angle.So whilst Casio's FX-991ES Plus might be less featured model, the font used is both bigger and clearer in style and that is a much better option in my view. If you need the feature set of the FX-991EX, either try it before you buy it or look elsewhere.

My mind is blown by the sheer amount of stuff that this little calculator can do! I'm gonna need a lot of practice and quality time with the manual...I wish I'd had this bad boy for my a-level exams for checking definite integrals and other stuffs like that.Display is also the highest resolution of a calculator I've had which is quite nice.Shame that the matrices only go up to 4x4.The design is reminiscent of carbon fibre and looks really clean, not tacky at all. Same for the metallic buttons which I was sceptical about at first.Overall, great buy.