Computing a basis for a field over $\mathbb{Q}$

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I'm working on the following homework question:

Let $F = \mathbb{Q}(i, \sqrt{3}, \omega)$ where $i \in \mathbb{C}$ such that $i^2 = -1$ and $\omega$ is a complex (nonreal) cube root of 1. Compute [F:$\mathbb{Q}$] and a basis for $F$ over $\mathbb{Q}$.

I'm just beginning to study Galois theory, so I'm very unfamiliar with how to start this type of problem, so any help would be appreciated.

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You should be able to work from the fact that we can choose $$\omega=e^{2i\pi/3}=-1/2+i\frac{\sqrt3}2$$ This is clearly contained in $\mathbb Q(i, \sqrt3) $, so you just have to find a basis of this. Can you prove that $1,i,\sqrt3,i\sqrt3$ form such a basis? The goal is to get all possible elements uniquely. You need to prove that you can get all elements of the field as a rational linear combination of these and no rational linear combination with nonzero coefficients yields zero.