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In this question I needed a way to denote an algebraic number using a polynomial equation it satisfies and its isolating polynomial. Because I am not aware of any commonly accepted notation for this, I resorted to an explanation in English.

But I recall that I saw somewhere a notation like this: $$\rho=\left[12\,x^8-12\,x^4-8\,x^2-1\right]_{1<x<2}$$

Is it commonly accepted and understandable? If not, can you suggest another good notation for that?

HWᅠ
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2 Answers2

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I have not seen the notation you have used. The easiest way is to write it out explicitly, i.e., $\rho$ is such that $\rho \in (1,2)$ and is a root of $f(x) = 12x^8 - 12 x^4 - 8x^2 - 1$.

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You can use the definite description quantifier. As in:

$$\mathop{\iota}_{x:(1,2)}(0=12x^8−12x^4−8x^2−1)$$

But, I prefer your notation.

goblin GONE
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