Recent questions tagged complex-number

Let $p\left ( z\right )=z^{3}+\left ( 1+j \right )z^{2}+\left ( 2+j \right )z+3$, where $z$ is a complex number.Which one of the following is true?$\text{conjugate}\:\lef...

For a complex number $z,\displaystyle{} \lim_{z \rightarrow i} \frac{z^{2}+1}{z^{3}+2z-i (z^{2}+2)}$ is$-2i$$-i$$i$$2i$

Square roots of $-i$,where $i=\sqrt{-1}$, are$i,-i \\$$\cos(-\dfrac{\pi }{4} )+i\sin(-\dfrac{\pi }{4})+\cos(\dfrac{3\pi }{4})+i\sin(\dfrac{3\pi }{4}) \\$$\cos(\dfrac{\pi ...