Let z1 and z2 be two complex numbers such that ${\overline z _1} = i{\overline z _2}$ and $\arg \left( {{{{z_1}} \over {{{\overline z }_2}}}} \right) = \pi$. Then :
Solution
<p>$\because$ ${{{z_1}} \over {{z_2}}} = - i \Rightarrow {z_1} = - i{z_2}$</p>
<p>$\Rightarrow \arg ({z_1}) = - {\pi \over 2} + \arg ({z_2})$ ..... (i)</p>
<p>Also $\arg ({z_1}) - \arg ({\overline z _2}) = \pi$</p>
<p>$\Rightarrow \arg ({z_1}) + \arg ({z_2}) = \pi$ ..... (ii)</p>
<p>From (i) and (ii), we get</p>
<p>$\arg ({z_1}) = {\pi \over 4}$ and $\arg ({z_2}) = {{3\pi } \over 4}$</p>
About this question
Subject: Mathematics · Chapter: Complex Numbers and Quadratic Equations · Topic: Modulus and Argument
This question is part of PrepWiser's free JEE Main question bank. 223 more solved questions on Complex Numbers and Quadratic Equations are available — start with the harder ones if your accuracy is >70%.