Brand: | Texas Instruments |
Model: | TI-25 |
Type: | Scientific calculator |
Batteries: | LR 44 x 2 |
Lifetime: |
Introduced: 1978 Terminated: unknown |
Notes: |
Black is beautiful, or at least someone at Texas Instruments must
have thought. A very dark design, hard to read when lighting is
poor. Called the "Slimline™ 25" in the calculator's manual.
This is a standard school calculator with all the required functions, including statistical functions. This calculator has some peculiar quirks. For instance, when you press π and then the "EE"-key to add an exponent, it will. No problem. I'm not sure however when you would need π multiplied by a factor of ten. So to enter π⋅10^{42} simply type "π", "EE", "4", "2". Another funny thing is the way it handles the "!" operator. As with all calculators with two-digit exponents it will calculate up to and including x! for any natural x in the range 0 ≤ x ≤ 69. For any natural x > 69 it will produce an error. However, for any natural x in the range 70 ≤ x ≤ 99 it will still try to calculate x! up to the moment it will encounter an internal error. For any natural x > 99 it will immediately give an error without trying to calculate x!. Maybe this way of handling x! has a smaller memory footprint or something. Thanks for this nice addition to the collection, Michel "Mikki" Waucomont! |
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©2009 Ernst Mulder