9.9 DECOMPOSE Operator

The decompose operator takes a multivariate polynomial as argument, and returns an expression and a list of equations from which the original polynomial can be found by composition. Its syntax is:

     decompose(exprn:polynomial):list.

For example:

     decompose(x^8-88*x^7+2924*x^6-43912*x^5+263431*x^4-
                    218900*x^3+65690*x^2-7700*x+234)
                   2                  2            2
          -> {u  + 35*u + 234, u=v  + 10*v, v=x  - 22*x}
                                     2
     decompose(u^2+v^2+2u*v+1)  -> {w  + 1, w=u + v}

Users should note however that, unlike factorization, this decomposition is not unique.

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