0
$\begingroup$

Given an entire function $f(z)$ we know that $$ \log f(z)=\log|f(z)|+i \arg f(z)$$

Let $f(z)=\frac{z-a}{z-\bar a}$, for complex number $a$. How to show that $\arg f(z)=\tan^{-1}(???)$ on the real line $\mathbb R$. (I don't know what is exactly inside $\tan^{-1}$)

  • 0
    $\tan^{-1}$ is a notation for the inverse function of $\tan$, in other words $\arctan$.2012-01-06

2 Answers 2