# complex numbers!

-2-2i
in polar form = 2.8 cis 2.35??

-3+4i polar form = 5 cis 2.2???

1 - sqaureroot(3i) polar form = 2 cis 1.04??

What is cis?

never mind I have the right answers.

polar form z = r (cos O + i sin O ) is also written in an abbreviated form
z = r cis O

cos + sin = cis

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