Complex Logarithm Homework: Find -Ln(1-e(iθ))

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Homework Statement


find -Ln(1-e(i\theta) (in terms of theta)

(this is me just skipping the part of the problem I know and going straight to what I can't figure out)

Homework Equations


ln(z) = ln(rei\theta)=Ln(r) + ln(ei\theta) = Ln(r) + i\theta

The Attempt at a Solution


I don't really know how to break this logarithm up into real and complex parts, the two ways I considered were

= -(Ln(1-1) + i\theta)
but that ends up with Ln(0) which blows up to infinity and doesn't make sense in this problem.

= -(Ln(1) + i\theta)
but this is just -i\theta which leaves only an imaginary part, and the problem implies there is a real logarithmic solution as well.
 
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hi soothsayer! :smile:

(have a theta: θ :wink:)

you need to express 1 - e in Cartesian form, a + ib :wink:
 
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