Get Help with Solving a Complex Equation: Tips and Tricks

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The discussion focuses on solving the equation involving complex numbers, specifically i Re z + Im \bar{z} + π = |z| + arg(z) with arg(z) in [0, 2π). Participants suggest expressing z in terms of its components x and y, leading to the realization that the equation can be simplified. A critical point is the identification that if x = 0, then arg(y/x) becomes undefined, but it can be approached as arctan(inf) = π/2. Ultimately, the solution is identified as z = 0 + i*(π/4). The conversation emphasizes the importance of analyzing the real and imaginary components in complex equations.
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Hello!
We've got to solve the following equation:
i \ Re \ z+Im \ \bar{z}+\pi=|z|+arg(z) with arg(z)\in[0,2\pi)
Please don't solve it for me. Give me a hint first.
 
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First write z= x+ iy= |z|(cos(arg z)+ i sin(arg z))
of course, |z|= \sqrt{x^2+ y^2} and arg z= arctan(\frac{y}{x}).
Now you can write the condition in terms of x and y.
 
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Ok, thanks...

Did you mean that arg(z)=arctan(y/x)?

Now it looks like this doesn't it?:
ix-y+\pi=\sqrt{x^2+y^2}+arctan\left(\frac{y}{x}\right)
or (-y-\sqrt{x^2+y^2})+ix=arctan\left(\frac{y}{x}\right)-\pi
Now it seems the number on the right is real, so the number on the left must be real too, so x=0, but then arctan(y/x) is not defined...hm...does it have any consequences?
 
Sure it does, arctan(inf)=pi/2 the answer is then seen to be z=0+i*(pi/4).
 
Ok, thanks guys! :)
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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