Re: TI85 Bug? 10^-1(e6) Incorrect Result???


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Re: TI85 Bug? 10^-1(e6) Incorrect Result???



Peter Chrisbacher wrote:
>
> My wife was doing some chemistry conversions when one of her
> calculations came up with the answer "0".  Her equation was similar to:
>
>         10^-1(10^6)
>
> This seems to be a operation processing order error to me; the
> calculator seems to be raising 10 to the -1e6th power, and getting 0 for
> an answer.  This seems incorrect to me.  I would expect the "^" would be
> evaluated first - e.g. (10^-1)*(e6).  In fact, when I key the equation
> in this way, I get the answer I would expect.
>
> Can anyone explain this apparent bug?  (Can you duplicate it?)
>
> thanks -
>
> -Pete

The bug lies in the TI's interpretation of the special minus (let's call
it "_")
from the TI-68 to the 85 a change was made.
On the 68 _2^2 would produce (_2)^2, but on the 85 and later, this
became _(2^2). In other words, the minus isn't always "carried over" as
one should expect.
Try this: 20+_2^2
One would expect 24, but the result is 16, because _2^2 is read as -4.
Therefore 10^_1(10^6) will produce nil.
If you try for instance 10^2(2+3) you get 500.

I suggest you use the rule used when programming: Rather a paranthesis
to many than one to little :-)

In fact, a good way to think is, how would you read it yourself?
I would frown if presented to an expression like 10^_1(10^6), since I
wouldn't know how to read it.

It's like computers: It wants details.

Upon checking I can see the problem doesn't occur on the TI-92, but then
again, it's a totally different interface ;-)

good luck :),

--
          Rene Kragh Pedersen
------------------------------------------------
.oO) Who is General Failure, and why is he reading my disk? (Oo.


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