Question

If $z=1-i,$ then principal value of $arg(z)$ equals to

• A. $-\frac{\pi }{4}$
• B. $\frac{\pi }{4}$
• C. $-\frac{7\pi }{4}$
• D. $Noneofthese$

Answer 1

Answer: (A)

Given, $z=1-i$ Here, given point z lies in IVth quadrant.
$\therefore$ $\arg (z)=-{\tan }^{-1}\left(\frac{1}{1}\right)$ $=-\frac{\pi }{4}$