MCQ
The argument of the complex number $ - 1 + i\sqrt 3 $ is ............. $^\circ$
  • A
    $-60$
  • B
    $60$
  • $120$
  • D
    $-120$

Answer

Correct option: C.
$120$
c
(c)$arg( - 1 + i\sqrt 3 ) = {\tan ^{ - 1}}\left( {\frac{{\sqrt 3 }}{{ - 1}}} \right) = {120^o}$
because it lies in second quadrant.

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