Comment #11 on issue 2895 by [email protected]: minpoly hangs on this expresion
http://code.google.com/p/sympy/issues/detail?id=2895

Every algebraic number has a minimal polynomial (algebraic number is defined as a root of a polynomial with rational coefficients). Algebraic numbers form a field, so sums, products, and integer powers of algebraic numbers are again algebraic. Rational powers will work as well, since one could just raise the power of each term in the polynomial that the base expression satisfies by the denominator (e.g., sqrt(2) + sqrt(3) satisfies x**4 - 10*x**2 + 1, so sqrt(sqrt(2) + sqrt(3)) satisfies x**8 - 10*x**4 + 1.

And note the distinction between satisfying a polynomial and that polynomial being the minimal polynomial. Every algebraic number satisfies many polynomials, but only one monic polynomial of minimal degree. That minimal polynomial will divide every other polynomial that the number satisfies, so finding it is just a matter of searching the irreducible factors.

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