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#### Search: #### Tellrat

Function: tellrat (<p_1>, ..., <p_n>) Function: tellrat () Adds to the ring of algebraic integers known to Maxima the elements which are the solutions of the polynomials <p_1>, ..., <p_n>. Each argument <p_i> is a polynomial with integer coefficients.

`tellrat (<x>)` effectively means substitute 0 for <x> in rational functions.

`tellrat ()` returns a list of the current substitutions.

`algebraic` must be set to `true` in order for the simplification of algebraic integers to take effect.

Maxima initially knows about the imaginary unit `%i` and all roots of integers.

There is a command `untellrat` which takes kernels and removes `tellrat` properties.

When `tellrat`ing a multivariate polynomial, e.g., `tellrat (x^2 - y^2)`, there would be an ambiguity as to whether to substitute `<y>^2` for `<x>^2` or vice versa. Maxima picks a particular ordering, but if the user wants to specify which, e.g. `tellrat (y^2 = x^2)` provides a syntax which says replace `<y>^2` by `<x>^2`.

Examples:

```          (%i1) 10*(%i + 1)/(%i + 3^(1/3));
10 (%i + 1)
(%o1)                      -----------
1/3
%i + 3
(%i2) ev (ratdisrep (rat(%)), algebraic);
2/3      1/3              2/3      1/3
(%o2)    (4 3    - 2 3    - 4) %i + 2 3    + 4 3    - 2
(%i3) tellrat (1 + a + a^2);
2
(%o3)                     [a  + a + 1]
(%i4) 1/(a*sqrt(2) - 1) + a/(sqrt(3) + sqrt(2));
1                 a
(%o4)           ------------- + -----------------
sqrt(2) a - 1   sqrt(3) + sqrt(2)
(%i5) ev (ratdisrep (rat(%)), algebraic);
(7 sqrt(3) - 10 sqrt(2) + 2) a - 2 sqrt(2) - 1
(%o5)    ----------------------------------------------
7
(%i6) tellrat (y^2 = x^2);
2    2   2
(%o6)                 [y  - x , a  + a + 1]```

There are also some inexact matches for `tellrat`. Try `?? tellrat` to see them.

```(%o1)                                true
(%i2) ```

### Related Examples

? tellrat;

Calculate

##### tellrat

? tellrat;

Calculate 