Cho X ( e j ω ) = e − j ω 2 s i n 3 ω Hãy xác định biểu thức đúng tính argument của X ( e j ⊕ )

$\text{a}\text{r}\text{g}\left[X\left(e{}^{j\omega }\right)\right]=-\frac{\omega }{2}+\left\{2k+\frac{1}{2}\left[1-\frac{\text{s}\text{i}\text{n}3\omega }{\left|\text{s}\text{i}\text{n}3\omega \right|}\right]\right\}\pi$

$\text{a}\text{r}\text{g}\left[X\left(e{}^{j\omega }\right)\right]=-\frac{\omega }{2}+\text{a}\text{r}\text{g}\left[\text{s}\text{i}\text{n}3\omega \right]$

$\text{a}\text{r}\text{g}\left[X\left(e{}^{j\omega }\right)\right]=\text{a}\text{r}\text{c}\text{t}\text{g}\frac{\text{I}\text{m}\left[X\left(e{}^{j\omega }\right)\right]}{\text{R}\text{e}\left[X\left(e{}^{j\omega }\right)\right]}$

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