Question

3-4i in polar form?

Answer 1

The easiest way to think of imaginary numbers in polar form is to think of "imaginary number" as the 'Y' Axis.

So you are 3 along the x axis, and down 4 on the y axis.
r^2 = x^2 + y^2
tan θ = y / x

I believe
x + yi=r(cos θ+i sin θ)

Solve for θ and r, and plug and chug.