Polar Coordinates Homework: Understanding Second Equation

rsaad
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Homework Statement



In the attachment, I do not understand how we got the second equation in terms of polar coordinates.




Homework Equations





The Attempt at a Solution




I tried doing it by writing z_dot = (...)z and then plugging in r* exp i theta, but to no avail.
 

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rsaad said:

Homework Statement



In the attachment, I do not understand how we got the second equation in terms of polar coordinates.

Homework Equations


The Attempt at a Solution

I tried doing it by writing z_dot = (...)z and then plugging in r* exp i theta, but to no avail.

Show how you tried it. z'=r'e^(iθ)+iθ're^(iθ). Try going straight from the "complex notation" to the "polar notation". Divide both sides by e^(iθ) and equate real and imaginary parts.
 
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