# In Complex Numbers

hi,

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Please show work attempting to the problem.

Please show work attempting to the problem.
I want the understanding of way that led us to this result

@m s a: yeah.. we get that.. and what we need is that you show that you've solved something in this problem.. or atleast made an effort in this direction.

@m s a: yeah.. we get that.. and what we need is that you show that you've solved something in this problem.. or atleast made an effort in this direction.
If I was knowing the way to what asked

Hootenanny
Staff Emeritus
Gold Member
m_s_a,

According to the https://www.physicsforums.com/showthread.php?t=5374" you are required to show an attempt or detail your thoughts on a homework question before we can provide assistance.

You just have some idea how to prove the identity or else you wouldn't have been asked to prove it.

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Dick
Homework Helper
m_s_a, if you are really blocked, tell us the relation between log and exp, and then reflect on it.

Dick
Homework Helper
Like this:
Things would go much faster if you could convey simple information in some other way besides .bmp attachments. Those have to be approved before anyone can see them.

m_s_a, if you are really blocked, tell us the relation between log and exp, and then reflect on it.
like this:

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Hootenanny
Staff Emeritus
Gold Member
m_s_a, can you write a general complex number, z, in exponential form?

HallsofIvy
Homework Helper
So you are saying
If y= ln(z) then z= ey

Now, if y= a+ bi, what is ey?
(and remember that ep+q= epeq)

I came to this result then do it is right or no ?

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HallsofIvy
Homework Helper
Is there some reason why you insist upon posting attachments after you have been told its a bad idea?
It's not all that difficult to type:
(this would look much nicer in LaTex but I have typed it in ASCII)
z= |z|e^(i theta)
ln z= ln |z| e^(i theta) (Well, ln z= ln(z e^(i theta)) is correct)
ln z= ln |z|+ ln(e^i theta)
ln z= ln |z|+ i ln(theta)

i.e. log(z)= ln z

Assuming that your textbook has specified a convention that natural logarithm applied to complex numbers will be designated by "log", which is implied by the question itself, then it is not correct to write "ln z". Other than that, what you wrote is correct.

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