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Topic: Strange result of solve
Replies: 2   Last Post: Mar 11, 2014 3:35 AM

 Messages: [ Previous | Next ]
 Matthias Bode Posts: 84 Registered: 3/16/05
Re: Strange result of solve
Posted: Mar 11, 2014 3:35 AM

Hola:

> I cannot really understand the different results of the following:>
> Solve[ 5 x == 0, x, Modulus-> 5 ]
> result: {{x-> 0}}
>
> and:
>
> Solve[ 0 x == 0, x, Modulus-> 5 ]
> result: {{}}
>
> The last means that every x is OK. Which I think is true. But I would
> expect the same result for the first case.

The result for the first case is the ring of integers.

Table[{x, Mod[5*x, 5]}, {x, -5, 5}]

{{-5, 0}, {-4, 0}, {-3, 0}, {-2, 0}, {-1, 0}, {0, 0}=
, {1, 0}, {2, 0}, {3, 0}, {4, 0}, {5, 0}}

Best regards,

MATTHIAS BODE.

Date Subject Author
3/11/14 Bob Hanlon
3/11/14 Matthias Bode