Multivariable double integrals using polar coordinates

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I have to calculate the following integral:

$$\int_{0}^{1}\int_{\sqrt{3x}}^{\sqrt{4-x^2}}x\sqrt{x^2+y^2}dydx$$

I drew the domain of integration, and I found that :
$$ 0 \leq r \leq 2 $$

$$0 \leq \theta \leq \pi/3$$

Assuming what I found is correct, I how can I rewrite the integral?

I know $ dydx $ becomes $rdrd\theta$, and $\sqrt{x^2+y^2}$ becomes $r$.

Do I convert $x$ to $rcos\theta$ ? This will yield me the answer of $2\sqrt{3}$ after integration, but I cant find any online calculator to verify this.

Thanks in advance!