Question

Express z1=0+10i in polar form.

Please help as I am confused on what to do as they have a 0 there and when I try plugging it in it is undefined as 10/0 is not possible.

Answer 1

radius is 10 units, direction straight up, theta = 90 degrees = pi/2 radians
cos theta = 0 (in x direction)
sin theta = 1 (in y direction)

Answer 2

by the way, yes tan theta = sin theta / cos theta = 1/0 = undefined.
That happens at 90 degrees :)