x^50-20x^32-3x+1 divideed by x+i
how do u divide by i? can some eplain please.
When dividing by a complex number, multiply the numerator and denominator by its conjugate.
For example:
$\displaystyle \frac{10}{4 + 2\,\text{i}}$
$\displaystyle =\frac{10\color{red}\left(4 - 2\,\text{i}\right)}{\left(4 + 2\,\text{i}\right)\color{red}\left(4 - 2\,\text{i}\right)}$
$\displaystyle =\frac{\color{red}40 - 20\,\text{i}}{\color{red}16 - 4\,\text{i}^2}$
Noting that $\displaystyle \text{i}^2 = -1$, we have
$\displaystyle \frac{40 - 20\,\text{i}}{16 - {\color{red}(-1)}4}$
$\displaystyle =\frac{40 - 20\,\text{i}}{\color{red}20}$
$\displaystyle =\frac{40}{20} - \frac{20\,\text{i}}{20}$
$\displaystyle =2 - \text{i}$
Does that help?