How do you multiply $(-1+2i)(3+2i)$ in trigonometric form?

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Answer 1 · 2017-12-30T13:02:47

$-7+4iota$

$iota= sqrt(-1)$
So, $iota^2=-1$

$(-1+2iota) (3+2iota)$

$-3-2iota+6iota-4$

$-7+4iota$

Simply multiply as we generally multiply polynomial by polynomial provided the rules of complex must in mind just like $iota^2=-1$ .

How do you multiply (-1+2i)(3+2i) (-1+2i)(3+2i) in trigonometric form?