Remark — A look ahead: complex numbers

In the chapter on complex numbers the polar coordinate of z=x+iyz = x+iy is precisely the pair (ρ,θ)(\rho,\theta): z=ρ(cosθ+isinθ)=ρeiθz = \rho(\cos\theta + i\sin\theta) = \rho\,e^{i\theta} (Euler’s form). Polar coordinates are therefore the natural language for multiplying complex numbers and raising them to powers.

Topics: Goniometry
Concepts: Polar coordinates · Complex numbers · Cartesian plane