Solve Modulus for (3-4i)^10/(2-i)^8

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To find the modulus of (3 - 4i)^10/(2 - i)^8, the initial approach involved converting the complex numbers into their exponential forms. The modulus of 3 - 4i is correctly identified as 5, while the modulus of 2 - i is √5. There was confusion regarding the use of exponents in polar form and the distinction between modulus and conjugate. Ultimately, the modulus can be calculated directly without needing to convert to Cartesian form. The discussion highlights the importance of understanding the definitions and properties of complex numbers.
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Homework Statement


Find the modulus for:
(3 - 4i)^10/(2 - i)^8

Homework Equations





The Attempt at a Solution


I tried putting the two terms in their exponential forms. Then do simple exponential operations and convert back to cartesian form to get the modulus.
3 - 4i = 5e^{arctan(-4/3)}
2 - i = \sqrt{5}e^{arctan(1/2)}

However the arguments aren't going to be exact numbers. Is there another way to approach this question?
 
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hadroneater said:

Homework Statement


Find the modulus for:
(3 - 4i)^10/(2 - i)^8

Homework Equations





The Attempt at a Solution


I tried putting the two terms in their exponential forms. Then do simple exponential operations and convert back to cartesian form to get the modulus.
3 - 4i = 5e^{arctan(-4/3)}
2 - i = \sqrt{5}e^{arctan(1/2)}

However the arguments aren't going to be exact numbers. Is there another way to approach this question?

You left out an i on your exponents in polar form. But that's besides the point. Don't you think modulus of 3-4i would just be 5? Why or why not?
 
Right. I confused the definition of Modulus with Conjugate. Man, I feel stupid.

Thanks!
 
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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