Question
If $|z|=r$ and $\arg (z)=\frac{\pi}{4}$, then $\left|z+\frac{1}{z}\right|$ equals(a) $\mathrm{r}+\frac{1}{\mathrm{r}}$(b) $\sqrt{r^{2}+\frac{1}{r^{2}}}$(c) $\sqrt{\mathrm{r}+1 / \mathrm{r}}$(d) $\sqrt{r^{2}+1 / r^{2}-2}$
Step 1
From the property of complex numbers, we know that $|1/z| = 1/|z|$ and $\arg (1/z) = -\arg (z)$. Show more…
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