# How do you divide ( 7i-5) / (2i+1) in trigonometric form?

In trigonometric form $- 3.85 \left(\cos 242.1 + i \sin 242.1\right)$
$\frac{7 i - 5}{2 i + 1} = \frac{\left(7 i - 5\right) \left(2 i - 1\right)}{\left(2 i + 1\right) \left(2 i - 1\right)} = \frac{- 14 + 5 - 17 i}{- 4 - 1} = - \frac{1}{5} \cdot \left(- 9 - 17 i\right)$
$r = \sqrt{{9}^{2} + {17}^{2}} = 19.24$ $\theta = 180 + {\tan}^{-} 1 \left(\frac{17}{9}\right) = {242.1}^{0}$ As it is on 3rd quadrant 180 has been added.
In trigonometric form : $- \frac{19.24}{5} \left(\cos 242.1 + i \sin 242.1\right)$
or$- 3.85 \left(\cos 242.1 + i \sin 242.1\right)$[Ans]