1. The problem statement, all variables and given/known data What is the polar form of the complex number 3-4i? 2. Relevant equations z=r*cos(theta)+i*r*sin(theta) 3. The attempt at a solution 5(cos(arctan(-4/3))-i*sin(arctan(-4/3))) This is what I thought the correct answer would be, but it was a multiple choice quiz and this was not one of the options. The correct answer, according to the quiz, was 5(3/5-i*4/5). I don't see how that is in polar form, since the cos and sin of theta were both evaulated. If that is actually correct, then couldn't you simply make any standard complex number polar form by factoring out r?