Re: 83 versions
[Prev][Next][Index][Thread]
On Aug 12, Mark Malley wrote:
> DA>Geez, all I have is 1.010.
>
> DA>Can sombody with a higer rom vers. do this problem and tell me the result,
> DA>please?
>
> DA>i^7
>
> -3E-13-i the first two - are negative the last one is minus! I have
> 1.0200
This result is due to rounding error. Mathematically, i^7 should be
"0 - i", but instead the TI-83 gives "-3E-13 - i", which is "-
0.0000000000003 - i", which is pretty close, but not perfect. For
another (similar) example, try
sin(0)
sin(pi)
sin(2pi)
sin(3pi)
sin(4pi)
on a TI-82 or TI-83.
I wouldn't expect the i^7 problem to be "fixed" in future ROM
versions -- users have to expect rounding errors. Rounding error
frequently leads to inaccurate results, and it pays to keep in mind
that it is always a possibility when doing numerical calculations on
a calculator or computer. And rounding errors do not always lead to
answers that are only off by a little -- sometimes they have larger
consequences (sorry I don't have any immediate examples of this).
------------------------------------------------------------------
Evan Romer Susquehanna Valley HS
sv_golden@SUNYbroome.edu Conklin NY 13748
References: