281–290 of 503 posts
My TI-85 story. While I was in prison, around 1996 or 1997, I found out a friend had a TI-85 calculator. I realized it was programmable, so I borrowed it over the weekend and wrote a program to track his stock portfolio. It was the first time I had programmed anything in 2 or 3 years. Then I learned that the US Bureau of Prisons had a rule against any calculator (or device) that was "programmable". So I programmed th…
We had to buy those calculators for highschool and it was a waste of money, felt like somebody must be paying somebody off to have thousands of students buy a device that they will certainly never have to use (and is of little educational value).
My TI-85 story. While I was in prison, around 1996 or 1997, I found out a friend had a TI-85 calculator. I realized it was programmable, so I borrowed it over the weekend and wrote a program to track his stock portfolio. It was the first time I had programmed anything in 2 or 3 years. Then I learned that the US Bureau of Prisons had a rule against any calculator (or device) that was "programmable". So I programmed th…
They had TI-85's in late '90s? I remember there only being TI-83s.
I'm thinking something that could be a major upgrade in spirit to the long-in-the-tooth (released a decade ago) Casio FX-CG500.
Could use the soon to be released ARM C-1 Nano and Pro cores in an SoC with stacked 2GB LPDDR4, USB-C charging to a large battery, high-res transflective LCD...
Mockup "AxiomPad Pro X1": https://enia.cc/out/axiompad-cas-mock.png
My TI-85 story. While I was in prison, around 1996 or 1997, I found out a friend had a TI-85 calculator. I realized it was programmable, so I borrowed it over the weekend and wrote a program to track his stock portfolio. It was the first time I had programmed anything in 2 or 3 years. Then I learned that the US Bureau of Prisons had a rule against any calculator (or device) that was "programmable". So I programmed th…
They had TI-85's in late '90s? I remember there only being TI-83s.
TI-81 (1990)
TI-85 (1992)
TI-82 (1993)
TI-80 (1995)
TI-92 (1995)
TI-83 (1996)
TI-86 (1996)
TI-73 (1998)
TI-83 Plus (1999)
TI-89 (1998)
TI-92 Plus (1998)
TI-83 Plus Silver Edition (2001)
TI-84 Plus (2004)
TI-84 Plus Silver Edition (2004)
Earlier quoted context omitted.
There is no graphing problem that you'll be asked to solve before university that can't be plotted to a 'good enough for high school' level by hand in seconds . 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, becau…
This is nonsense. Kids are not expected to look at polynomial equations and be able to deduce the shape of the graph without a graphing calculator. Besides, it is expected that a student can use a graphing calculator to be able to numerically solve for a root of arbitrary polynomial equation.
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.
Earlier quoted context omitted.
On 9 July 1537, Martin Luther wrote in a letter to Wolfgang Capito about a lost golden ring: "Pro annulo aureo gratias tibi agit mea Catharina, quam vix unquam magis indignatam vidi, quam ubi sensit, cum vel furto sublatum, vel sua negligentia (quod nec mihi verisimile est, licet usque ingerenti) amissum, quod persuaseram ei, hoc donum esse felix omen et augurium ei missum, tanquam nunc certum esset, vestram Ecclesia…
If my grandmother were to find out that housekeepers occasionally do actually take things, it would set us back decades.
My Catherine thanks you for the golden ring, whom I have hardly ever seen more indignant than when she realized that it had been stolen or lost through her own negligence (which is not likely for me, although I still insist on it), which I had persuaded her that this gift was a happy omen and augury sent to her, as if it were now certain that your Church would agree pleasantly with ours; this grieves the woman wonderfully.
Ti really needs to stop with the artificial product differentiation. There's no reason 15 years after the Nspire CX CAS came out that everyone of their calculators can't do CAS.
Honest question: Why do we need physical graphing calculators anymore? Can't this just be a phone app? That screen resolution for one is horrible for 2026.
As an engineering student at CMU, I had an HP 15c like everyone else. A few years back when I found out they are coveted, I sold mine on ebay. I have an emulator on my phone.
I assume that calculators will continue to evolve and that my grandchildren will have a Propædeutic Enchiridion.
