Complex Numbers · NDA previous year questions

2020 2 questions

1. Q452020 · 6 Sept 2020

   What is the argument of the complex number $\frac{1-i\sqrt{3}}{1+i\sqrt{3}}$, where $i=\sqrt{-1}$ ?

   1. A.$240^{\circ }$
   2. B.$210^{\circ }$
   3. C.$120^{\circ }$
   4. D.$60^{\circ }$
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   Answer: A

2. Q462020 · 6 Sept 2020

   What is the modulus of the complex number $\frac{\cos \theta +i\sin \theta }{\cos \theta -i\sin \theta }$, where $i=\sqrt{-1}$ ?

   1. A.$\frac{1}{2}$
   2. B.1
   3. C.$\frac{3}{2}$
   4. D.2
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   Answer: B