Complex Variables (Finding complex roots)

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The discussion centers on solving the equation (z² + 1)² = -1, which is a polynomial of degree 4. The initial approach involved factoring, leading to the expression z² = -1 ± i. Participants emphasized the importance of finding the square roots of complex numbers to determine all four roots. The final solutions were identified as ±√(21/4) * exp(i3π/8) and √(21/4) * exp(i5π/8). The exchange highlights the collaborative effort in solving complex variable equations.
Polamaluisraw
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Homework Statement


Find all solutions to (z2+1)2=-1


The Attempt at a Solution


I know that because it is a polynomial of degree 4 it is a square inscribed inside of a circle in the complex plane. All i really need is one solution and from that finding the other three is easy. I have tried factoring it numerous ways. the best I get it to is

z2= i -1

thank you!
 
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Don't you get ##z^2=-1\pm i##? Do you know how to find the square roots of a complex number? That would give you your four roots.
 
LCKurtz said:
Don't you get ##z^2=-1\pm i##? Do you know how to find the square roots of a complex number? That would give you your four roots.

wow i completely left of the ± that is my problem! Let me work it and ill report back, thank you!
 
got it,

±21/4*exp(i3\pi/8)
21/4*exp(i5\pi/8)

thank you again
 
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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