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Casio FX991ES Plus - Inputting recurring decimals?

Hi there,

I broke my FX 85GT Plus and I am looking at the FX991ES Plus (The grey one with the functions like integrals etc.) however looking at the image, I can't see a recurring decimal input button like the FX 85GT does which is the more basic model. Can anyone verify this before I buy it?

Thanks

Edit: Also I am planning to do A2 Maths next year as well - Do the extra functions help? I also have a Stats exam on the 15th so I'm wondering if it will help for that too i.e. to check answers
(edited 7 years ago)
Original post by CrazyFool229
Hi there,

I broke my FX 85GT Plus ...


What does the recurring decimal input button look like?

The extra functions only have one use when it comes to exams, at least for me, and that is checking your answer.

First thing, you need to show working when doing integrals and differentiation, so you can't just put the answer down.

Second, most of the time they'll give you your answer in decimals, and the examiners will want exact answers a lot of the time; example, the exam wants pi and the calculator gives you 3.14... .

Third, it takes some time for the calculator to do these extra functions, and depending on how complicated, it might not even work.

About the statistics, some people do get a use out of that, I however don't. For example some people use it instead of the tables you have at the end, I find the tables much faster. It is very annoying navigating between modes that it's much easier to do by hand. Also the examiners will want working, so if you're going to do it by hand anyways.

All that still doesn't mean that it's a bad calculator, just that in exam conditions some of these extra functions are a bit of hassle.
Reply 2
If you want to input a repeating decimal why not just put it in as a fraction instead?
Original post by gagafacea1
What does the recurring decimal input button look like?

The extra functions only have one use when it comes to exams, at least for me, and that is checking your answer.

First thing, you need to show working when doing integrals and differentiation, so you can't just put the answer down.

Second, most of the time they'll give you your answer in decimals, and the examiners will want exact answers a lot of the time; example, the exam wants pi and the calculator gives you 3.14... .

Third, it takes some time for the calculator to do these extra functions, and depending on how complicated, it might not even work.

About the statistics, some people do get a use out of that, I however don't. For example some people use it instead of the tables you have at the end, I find the tables much faster. It is very annoying navigating between modes that it's much easier to do by hand. Also the examiners will want working, so if you're going to do it by hand anyways.

All that still doesn't mean that it's a bad calculator, just that in exam conditions some of these extra functions are a bit of hassle.


Hi - The reason why I wanted to get the "upgraded" model is purely so I can check answers as well. Obviously there are method marks and anyway I would be too paranoid to rely on my calculator to just produce an answer for complex calculations!

The recurring decimal button just looks like a yellow box with a dot on the top above the x^2 button on the Casio FX-85GT and it doesn't have it on the FX991ES Plus from looking at the picture.

Original post by offhegoes
If you want to input a repeating decimal why not just put it in as a fraction instead?

I can do that as well - I'm just used to having that button on the calculator before it broke. I guess I could always put it in as a fraction as you suggested.
Original post by CrazyFool229
Hi - The reason why I wanted to get the "upgraded" model is purely so I can check answers as well. Obviously there are method marks and anyway I would be too paranoid to rely on my calculator to just produce an answer for complex calculations!

The recurring decimal button just looks like a yellow box with a dot on the top above the x^2 button on the Casio FX-85GT and it doesn't have it on the FX991ES Plus from looking at the picture.


Okay so apparently there is a model that has the recurring decimals AND integration:


You need to press alpha then square root.

This is fx99de-plus, as you can see from the picture. It's about £25, however there is a newer model fx-991 DE X.
I'll let you choose, this is the amazon page of the one above: https://www.amazon.co.uk/Casio-FX-991DE-Scientific-Calculator-Natural/dp/B0050OTQ42/ref=sr_1_1?ie=UTF8&qid=1464445676&sr=8-1&keywords=fx-991+DE

And this is of the Classwiz (X) model: https://www.amazon.co.uk/Classico-Scientific-Calculator-Natural-Display/dp/B00VB2ISDM/ref=sr_1_2?ie=UTF8&qid=1464445676&sr=8-2&keywords=fx-991+DE

By the way, the DE models have A LOT more features than the EX models.
(edited 7 years ago)
Reply 5
On the FX 85GT Plus, if you spam the recurring number about 15 times then the calculator takes it as a recurring number - I'm guessing this could be the same on other Casio models as well.
Original post by gagafacea1
Okay so apparently there is a model that has the recurring decimals AND integration:


You need to press alpha then square root.

This is fx99de-plus, as you can see from the picture. It's about £25, however there is a newer model fx-991 DE X.
I'll let you choose, this is the amazon page of the one above: https://www.amazon.co.uk/Casio-FX-991DE-Scientific-Calculator-Natural/dp/B0050OTQ42/ref=sr_1_1?ie=UTF8&qid=1464445676&sr=8-1&keywords=fx-991+DE

And this is of the Classwiz (X) model: https://www.amazon.co.uk/Classico-Scientific-Calculator-Natural-Display/dp/B00VB2ISDM/ref=sr_1_2?ie=UTF8&qid=1464445676&sr=8-2&keywords=fx-991+DE

By the way, the DE models have A LOT more features than the EX models.


That does seem nice especially with the extra functions like GCD etc. However it is In German which is annoying D: Thanks for the help :biggrin:
Original post by CrazyFool229
That does seem nice especially with the extra functions like GCD etc. However it is In German which is annoying D: Thanks for the help :biggrin:


Yeah i was just about to edit my post to warn you that it's in german. Damn Casio, why don't they make one for us? Especially the new classwiz thing, it looks so good! I might actually get it, I don't mind the german tbh
Original post by gagafacea1
Yeah i was just about to edit my post to warn you that it's in german. Damn Casio, why don't they make one for us? Especially the new classwiz thing, it looks so good! I might actually get it, I don't mind the german tbh


The ClassWiz thing does look pretty good - Especially the display! I will have a look. Do you/anyone else know if it is allowed in the Edexcel AS Mathematics exams? It can't do symbolic integration but I just want to check
Original post by CrazyFool229
The ClassWiz thing does look pretty good - Especially the display! I will have a look. Do you/anyone else know if it is allowed in the Edexcel AS Mathematics exams? It can't do symbolic integration but I just want to check


It should be, calculators that can do symbolic stuff are very very expensive, they have computer algebra systems. Example: https://www.amazon.co.uk/Texas-Instruments-TI-89-Calculator/dp/B0001EMLZ2/ref=sr_1_9?ie=UTF8&qid=1464446695&sr=8-9&keywords=calculator+algebra
Original post by gagafacea1
It should be, calculators that can do symbolic stuff are very very expensive, they have computer algebra systems. Example: https://www.amazon.co.uk/Texas-Instruments-TI-89-Calculator/dp/B0001EMLZ2/ref=sr_1_9?ie=UTF8&qid=1464446695&sr=8-9&keywords=calculator+algebra


That thing reminds me of my label maker somewhere in my drawers...

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