First, the radius should always be positive. Therefore
Second, the angle you should have gotten is in the third quadrant, since both a and b are negative. This gives an original angle of .
This should help get you the correct answer.
Find all the roots in rectangular coordinates, exhibit them as vertices of certain squares, and point out which is the principal root.
The given answer is , but I just do not see at all how they arrive at that answer. Here's what I got:
Switching back to rectangular coordinates gives:
This is clearly not correct, and my eyes are beginning to glaze over from looking at this problem all day. What am I doing wrong?