How to determine coefficients of the polynomial about $\alpha$ which represent $w \in \mathbb{Q}[\alpha]$?

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Let $\mathbb{Q}$ be the field of rationals and $\alpha$ be an irrational number which is not algebraic over $\mathbb{Q}$. Then for arbitrary element $w \in \mathbb{Q}[\alpha]$, there exists an unique polynomial $P$ with $P(\alpha)=w$.

My question is the following:

Given $\alpha$ and $w$, is it possible to determine the polynomial $P$ with 'basic' operations in $\mathbb{R}$, such as addition, multiplication, square root, the limit of some sequences, or etc?

Thinking $\mathbb{Q}[\alpha]$'s basis as $\{1, \alpha, \alpha^2, \cdots \}$, then the problem is equivalent to:

Can we represent the ordinary inner product in $\mathbb{Q}[\alpha]$ with respect to basis $\{1, \alpha, \alpha^2, \cdots \}$ with 'basic' operations in $\mathbb{R}$ ?

If then, we can determine coefficients of $P$ by calculating the inner product between $w$ and $\alpha^n$.

If it cannot be represented by 'basic' operations, what other methods or algorithms can be tried to find $P$ or its coefficients?