🚀 go-pugleaf

These flaws that we live with have a silver lining. They remind our
students that they need to be smarter than the calculator. It is an
awesome tool, but not a replacement for a sound understanding of the
mathematics being pursued.


Michael Butler
College of the Redwoods
Eureka Ca
Vremri@axe.Humboldt.edu


On Wed, 23 Nov 1994, RWWT wrote:

>
>
> Rick Seiden writes:
>
> > I have found an error on the TI-81.  If you set the mode to radians,
> and take
> > the tangent of pi, you get some really small number (I dont have an
> 81 in front
> > of me, so I don't know what the number is....also, I am not sure if
> that what
> >produces the error).  I have checked both the 82 and the 85, and did not
> >find this error in either.
>
> There is an interesting point here.  You would _expect_ the calculated
> result of an expression such as tan(pi) not to be exactly zero.  After
> all, there is no way to store (or pass along) an _exact_ representation
> of the irrational number pi.  I also do not have a TI-81 in front of me,
> but I notice that the TI-82 does seem to evaluate tan(pi) and sin(pi) to
> exactly zero.  I assume a more sophisticated algorithm was built into
> the 82 and 85.
>
> What is more, the expression sin(1000000*pi) also evaluates to an exact
> value of zero!  Very good.  BUT, sin(1000001*pi) yields -4.64102e-8 .
> Well, I guess we can stand it....
>
>
>         ||      RWW Taylor                 rwtnts@rit.edu
>         ||      National Technical Institute for the Deaf
>         ||      Rochester Institute of Technology
>         ||      Rochester NY 14623
>