This is part of an exam preparation:
Prove/contradict:
- If $L_1/K$ and $L_2/K$ are not Galois, then $L_1L_2/K$ is not Galois.
- If $L_1/K$ and $L_2/K$ are not solvable Galois extensions, then $L_1L_2/K$ is not a solvable Galois extension.
For 1, I think that the answer is false. I thought of "splitting" the splitting field of a polynomial. For example, the splitting field of $X^3-2$ over $\mathbb{Q}$ is $\mathbb{Q}(2^{1/3},\omega)$ and then taking $\mathbb{Q}(2^{1/3})$ and $\mathbb{Q}(\omega)$. The problem is that $\mathbb{Q}(w)/\mathbb{Q}$ is Galois and I can't think of a different kinds of example.
For 2, I think that the answer is true. We have $$G_1 = Gal(L_1L_2/K) \leq Gal(L_1/K) \times Gal(L_2/K) = G_2$$
Then I thought of making some claim about a subgup of a solvable group but Im not really sure how to proceed.
Thanks.
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