Complex Number (Modulus/Phase)

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The discussion focuses on finding the modulus and phase of the complex number given by the equation zθ₀² / (-θ² + 2iθθ₀φ + θ₀²). The user attempts to isolate the real and imaginary parts and uses the conjugate to simplify the expression but struggles with the modulus calculation, resulting in a complex expression that does not simplify easily. There is a question raised about whether a mistake was made or if a simpler method exists for this calculation. Additionally, a clarification is sought regarding the application of modulus and phase to the equation as a whole. The thread highlights the challenges in handling complex numbers and the need for clear definitions in mathematical contexts.
Air
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Homework Statement


Equation: \frac{z\theta_0^2}{-\theta^2+ 2i\theta\theta_0\phi+\theta_0^2}

Where z, \ \phi are constant and \theta_0 is the initial theta. Find the modulus and the phase associated with this equation.


Homework Equations


\frac{z\theta_0^2}{-\theta^2+ 2i\theta\theta_0\phi+\theta_0^2}


The Attempt at a Solution


To find the modulus, I separated the equation into real and imaginary and multiplied by the conjugate of the imaginary number to get it in the numerator and I got: =\frac{z\theta^2\phi - z\theta_0^2\phi}{\theta\phi} - \frac{z\theta_0}{2\theta\phi}i. When doing the modulus, I get: \sqrt{\frac{4z^2\phi^2\theta^4-8\phi^2z^2\theta^2\theta_0^2+ 4z^2\theta_0^4\phi^2 +z^2\theta_0^2}{4\theta^2}\phi^2} and this doesn't seem to simplify too well. Have I made a mistake or is there an easier method which I have missed? :confused: Thanks in advance for the help.
 
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Air said:

Homework Statement


Equation: \frac{z\theta_0^2}{-\theta^2+ 2i\theta\theta_0\phi+\theta_0^2}

Where z, \ \phi are constant and \theta_0 is the initial theta

Find the modulus and the phase associated with this equation.
Modulus and phase apply to a single complex number. What do you mean by "modulus and phase associated with this equation"?


Homework Equations


\frac{z\theta_0^2}{-\theta^2+ 2i\theta\theta_0\phi+\theta_0^2}


The Attempt at a Solution


To find the modulus, I separated the equation into real and imaginary and multiplied by the conjugate of the imaginary number to get it in the numerator and I got: =\frac{z\theta^2\phi - z\theta_0^2\phi}{\theta\phi} - \frac{z\theta_0}{2\theta\phi}i. When doing the modulus, I get: \sqrt{\frac{4z^2\phi^2\theta^4-8\phi^2z^2\theta^2\theta_0^2+ 4z^2\theta_0^4\phi^2 +z^2\theta_0^2}{4\theta^2}\phi^2} and this doesn't seem to simplify too well. Have I made a mistake or is there an easier method which I have missed? :confused: Thanks in advance for the help.
 
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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