If z=r(cos θ + isin θ), where r>0 and 0< θ < 1/2π, find in terms of r and θ the modulus and principal argument of....
I started off by: -z=-r(cos θ + isin θ) ---> = r(-cos θ - isin θ) = r(-cos(-θ) + isin (-θ)).
a= -rcos -θ b= rsin -θ
√(-rcos(-θ))^2 + (rsin (-θ))^2) = r
I have no idea how to continue from this. I know the formula for the argument is --> tan θ = b/a
Plugging in the values I have would result in tan θ = -tan -θ
The answer is supposed to be Mod= r Arg= θ - π