- #1
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Homework Statement
if z = -2 + 2i
find r and θ
The Attempt at a Solution
our teacher told us that when we have z = a + bi
r = sqrt(a^2 + b^2)
and θ = tan^-1(b/a)
so here it's supposed to be r = sqrt(8) and θ = - pi/4
but using wolfram alpha to see if the results are matching I get that
sqrt(8)*e^(i*-pi/4) is 2 - 2i
what am I doing wrong? I guess this has to do with the θ, but since it's always tan^-1(b/a) why am I getting different results?