Euler Equation -- diff. equations hw

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The discussion revolves around solving the differential equation (t-2)²y'' - 2(t-2)y' + 2y = 0 for t > 2. Participants suggest using a solution of the form y = (t-2)ᵖ to find the indicial polynomial's roots. This approach proves successful, leading to further inquiries about its rationale and derivation from textbooks. The importance of understanding the method rather than memorizing formulas is emphasized, with recommendations for online resources due to the lack of required textbooks. Overall, the conversation highlights effective problem-solving strategies in differential equations.
Arij
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Homework Statement


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Consider the differential equation (t-2)2y"-2(t-2)y'+2y=0, t>2

Find r+,r-roots of the indicial polynomial of the equation above.

Homework Equations


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Screen_Shot_2016_07_30_at_2_16_21_PM.png


The Attempt at a Solution



y'-[2/(t-2)]y'+[2/(t-2)^2]y=0

but then I am confused on how to set p(r), what do I do with the t in my a1 and a0thanks in advance :)
 
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I think that if, instead of trying to plug in numbers in formulas, you try plugging in a solution of the form ##y=(t-2)^r## and see what happens you will answer your own question.
 
LCKurtz said:
I think that if, instead of trying to plug in numbers in formulas, you try plugging in a solution of the form ##y=(t-2)^r## and see what happens you will answer your own question.

oh wow, that's brilliant! it worked! but can you explain more on why you chose this approach?

thank you :smile:
 
Arij said:
oh wow, that's brilliant! it worked! but can you explain more on why you chose this approach?

thank you :smile:

If you look in your text where they derive the indicial equation, I bet you will find that a substitution like that is where the indicial equation comes from. This is an example where it is much better to understand the method than to memorize the resulting formula.
 
LCKurtz said:
If you look in your text where they derive the indicial equation, I bet you will find that a substitution like that is where the indicial equation comes from. This is an example where it is much better to understand the method than to memorize the resulting formula.

Ops my bad. it's just that we were not required to get a textbook for the class and I was only referring to my notes.
is there any book you recommend?
 
Arij said:
Ops my bad. it's just that we were not required to get a textbook for the class and I was only referring to my notes.
is there any book you recommend?

There are lots of online notes about it. One such is
http://math.arizona.edu/~rjenkins/files/422/hw6soln.pdf
 
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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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