Polar cis form is the polar form of a complex number: r(cosθ+isinθ) often abbreviated as r cis θ
Explanation: A complex number z is always expressible uniquely as a+ib, where a,b∈R. That is it is expressible as a point (a,b) in R×R. Any such point can also be represented using polar coordinates as (rcosθ,rsinθ) for some radius r≥0 and angle θ∈R. The point #(r cos theta, r sin theta) corresponds to the complex number: rcosθ+risinθ=r(cosθ+isinθ) Given z=a+ib, we can calculate a suitable r, cosθ and sinθ ... r=√a2+b2 cosθ=ar sinθ=br One of the nice things about cosθ+isinθ is Euler's formula: cosθ+isinθ=eiθ So polar cis form is equivalent to reiθ

Comments