I guess my question is the Title.
I have been wondering how to prove that, knowing that my intuition comes from the :
You can build your number from the rationals, by taking finite roots, adding, substracting...
But how does the actual, field theoretical argument go ?
2026-04-02 07:23:21.1775114601
Proof that $\alpha$ is constructible $\iff$ there exists a finite tower of degree two extensions.
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