Let $z$ be complex number satisfying $|z|^3+2 z^2+4 z-8=0$, where $\bar{z}$ denotes the complex conjugate of $z$. Let the imaginary part of $z$ be nonzero.
Match each entry in List-$I$ to the correct entries in List-$II$.
List-$I$ | List-$II$ |
($P$) $|z|^2$ is equal to | ($1$) $12$ |
($Q$) $|z-\bar{z}|^2$ is equal to | ($2$) $4$ |
($R$) $|z|^2+|z+\bar{z}|^2$ is equal to | ($3$) $8$ |
($S$) $|z+1|^2$ is equal to | ($4$) $10$ |
($5$) $7$ |
The correct option is:
$(\mathrm{A})(\mathrm{P}) \rightarrow(1)(\mathrm{Q}) \rightarrow(3)(\mathrm{R}) \rightarrow(5)(\mathrm{S}) \rightarrow(4)$
$(\mathrm{P}) \rightarrow(2)(\mathrm{Q}) \rightarrow(1)(\mathrm{R}) \rightarrow(3) (S) \rightarrow (5)$
$(P) \rightarrow (2) (Q) \rightarrow (4) (R) \rightarrow (5) (S) \rightarrow (1)$
$(\mathrm{P}) \rightarrow(2)(\mathrm{Q}) \rightarrow(3)(\mathrm{R}) \rightarrow(5)(\mathrm{S}) \rightarrow(4)$
The sum of amplitude of $z$ and another complex number is $\pi $. The other complex number can be written
The amplitude of $\sin \frac{\pi }{5} + i\,\left( {1 - \cos \frac{\pi }{5}} \right)$
If $arg\,z < 0$ then $arg\,( - z) - arg\,(z)$ is equal to
Let $Z$ and $W$ be complex numbers such that $\left| Z \right| = \left| W \right|,$ and arg $Z$ denotes the principal argument of $Z.$
Statement $1:$ If arg $Z+$ arg $W = \pi ,$ then $Z = -\overline W $.
Statement $2:$ $\left| Z \right| = \left| W \right|,$ implies arg $Z-$ arg $\overline W = \pi .$
Let $S$ be the set of all complex numbers $z$ satisfying $\left|z^2+z+1\right|=1$. Then which of the following statements is/are $TRUE$?
$(A)$ $\left|z+\frac{1}{2}\right| \leq \frac{1}{2}$ for all $z \in S$ $(B)$ $|z| \leq 2$ for all $z \in S$
$(C)$ $\left|z+\frac{1}{2}\right| \geq \frac{1}{2}$ for all $z \in S$ $(D)$ The set $S$ has exactly four elements