Respuesta :

xy= (10-3i)(3-10i)
=30-100i- 9i+30i^2
=30^2-109i+30

Answer:  [tex]xy=-109i,[/tex]

and

[tex]\dfrac{x}{y}\dfrac{60}{109}+\dfrac{91}{109}i.[/tex]

Step-by-step explanation:  We are given two complex numbers as follows :

[tex]x=10-3i,~~~~~y=3-10i.[/tex]

To find [tex]xy[/tex] and [tex]\dfrac{x}{y}.[/tex]

We have

[tex]xy\\\\=(10-3i)(3-10i)\\\\=30-9i-100i+30i^2\\\\=30-109i-30\\\\=-109i,[/tex]

and

[tex]\dfrac{x}{y}\\\\\\=\dfrac{10-3i}{3-10i}\\\\\\=\dfrac{(10-3i)(3+10i)}{(3-10i)(3+10i)}\\\\\\=\dfrac{30-9i+100i-30i^2}{9-100i^2}\\\\\\=\dfrac{30+91i+30}{9+100}\\\\\\=\dfrac{60+91i}{109}\\\\\\=\dfrac{60}{109}+\dfrac{91}{109}i.[/tex]

Thus,

[tex]xy=-109i,[/tex]

and

[tex]\dfrac{x}{y}=\dfrac{60}{109}+\dfrac{91}{109}i.[/tex]