My lecturer stated that the principal argument is $[0,2\pi)$. However my tutor (my tutor is different to my lecturer) states that it is $(-\pi, \pi]$. Wikipedia article on complex numbers mentions both of these. In my test I used $[0,2\pi)$ convention and not the other one so my tutor deducted 0.5 mark. So which one is correct? and is it fair that I loose 0.5 mark here?
Is there any difference between principal argument and principal argument in the exponential polar form?