How do you multiply $(1-i)(-4-i)$ in trigonometric form?

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Answer 1 · 2016-09-30T06:31:38

You distribute it like any two factors.

$color(blue)((1-i)(-4-i))$

$= (1*-4)+(1*-i)+(-i*-4)+(-i*-i)$

$= -4 - i + 4i + i^2$

$= -4 + 3i - 1$

$= color(blue)(-5 + 3i)$

How do you multiply (1-i)(-4-i) (1-i)(-4-i) in trigonometric form?