Doesn't mean it's not overpriced, but that's one reason and you can get a used TI-83/84 for like $30 or less. They pretty much never break.
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1. Okay, the Casio can QR-code-link you to a graph, but if I have internet/smartphone there are better graphing tools anyway, like Desmos.
https://www.walmart.com/ip/Casio-FX-9750Glll-Graphing-Calcul...
The reason you can get used ti's for $30 is because that's how much they're actually worth.
You can get a catiga if you really want for like $17: https://www.aliexpress.us/item/3256809054964211.html
... or you can go with TI for $160 ...
https://www.amazon.com/Casio-fx-115ESPLS2-Advanced-Scientifi...
Includes GCD and LCM, some of the newer ones don't have them.
If you want graphing, there is the newish fx-CG100 has a nice display, but they removed Casio basic, it now only has micro Python (way too awkward to type on a tiny keypad):
https://www.amazon.com/Casio-ClassWiz%C2%AE-Calculator-Funct...
The older ones that still have basic:
https://www.amazon.com/Casio-fx-9750GIII-Graphing-Calculator...
BTW, here is a review I made of many calculators, measuring keyboard efficiency: (HP-15c still the best)
I used this on tests that banned the TI-89.
My Casio could do numeric differentiation and integration. I used this to double check my answers in my exams.
In fact, it still can as I still own and use it to this day.
It’s my favourite calculator and the one I always reach for, despite having a bunch of more complicated 2-line calculators etc. It’s just so easy to use and very fast to do anything I’d want with a calculator. If I need graphing I’ll reach for Desmos. If I need algebra I’ll use Sage. I haven’t used Sage since my undergrad, however.
[1] https://www.casio.com/content/dam/casio/product-info/locales...
[2] https://www.casio.com/ca-en/scientific-calculators/product.F...
Maybe everything is possible on the Casio, but it’s so much clearer on the NumWorks (especially for eg. Physics questions, where you might want to retrieve values you calculated earlier with full precision, etc). Genuinely felt like a cheat code when I was in highschool. I showed mine to my teacher and they swapped the whole’s schools standard calculators from the Ti-84 CE to the NumWorks, which is cheaper too.
I mean what do these do? I think like 10 digits worth?
If you're actually doing something requiring over 10 digits of accuracy and you can reliably hit that you probably have a $10 million lab...
So honestly what are we talking about here...If it's pure mathematics this is a bad tool for that as well.
In the exam, you'd also be at a disadvantage without advanced graphing.
Four data points is sufficient to give you a 'good enough' shape and position of a second-degree polynomial. Five or six for a third-degree one. (And you barely see them, and don't learn how to algebraically solve for their roots in high school anyways, because the cubic factoring formula is a pig.)
If you can't tell what a function's plotted shape is going to be at a glance, you haven't learned the material to the degree expected of an attentive child.
Personally, I found great enjoyment in coming up with more and more involved plots in the Polar and Parametric modes, where yes I would predict what a graph would look like and then go over to see it. And then go back and iterate. Etc. Until I was painting pictures with functions and had a far greater understanding of the domain than I’d wager anyone who thinks graphing calculations are for finding roots of polynomials could imagine.
It is not nonsense. I'll draft an example.
Any second degree polynomial is a parabola that is either pointing up (positive a term), or down (negative a term). That term is an indication of how curved it is.
-b/2a is the X coordinate of the parabola's inflection point.
Plug that value into the equation and it'll give you the Y coordinate.
You now know the inflection point of the parabola, you know which way it points, and how steep it is, and exactly where the polynomial's roots should live (and whether or not it has any real ones!). If you remember what the squares of 0.5, 1, and 2 are, you can now connect the dots on a 'pretty good' plot.
This took yuo longer to read than it takes to do.
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Similar transformations can be applied to sine waves, root functions, exponentials, logarithms, and reciprocals.
If you can't do this, or don't understand how to do this, you have not learned and understood the material. If all you've learnt is how to plug the formula into a magic $160 box to look at the pretty picture, and how to ask it to solve for roots, you and your teachers have wasted your time. The point of all this isn't looking at plots, the point is understanding how you can manipulate these equations, and what these manipulations do to them. This should all be drilled to the point of being intuitive.
Anything so complicated that basic algebraic manipulations won't get you the rough shape in seconds of work... Is more complicated than a high schooler is taught to solve.
I mean, these days kids have smartphones, what's the point of a graphing calculator?
Rant/Aside: Smartphones (or at least Android) are just generally really bad at being... smart, especially out of the box. No dictionary? No thesaurus? To say nothing of built-in encyclopedia (e.g. Wikipedia). Calculator worse than the $1 scientific ones? It's astounding how obvious it is that they're meant to dumb people down and just sell you crap when you look at the complete absence of basic functionality anyone from 50+ years ago might expect them to have.
Many tests will not allow you to use a smartphone. My son couldn't even use the school issued chromebook on his PSAT, he had to get a loaner Windows laptop or use an approved hard calculator.
However to answer your question: phone rules in classrooms vary enormously and the dedicated calculator is faster to interface when you're drilling problems in a homework setting
I finished highschool in the (gasp) 20th century so the modern classroom is certainly something I've had to learn
There isn't one.
The TI-83 is just a $160 tax on every high school student. There is precisely zero use in a graphing calculator before university.
If you ever need a plot of literally any function you'd be plotting in high school, you should be able to do a very quick, very rough approximation by hand. If you can't, you haven't learned the material.