Differential Equations: If y(1) =3 then y(1/2) = ?

Northbysouth
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Homework Statement


If y satisfies the differential equation:

ty'(t) + tln(t)y(t) = 0

and y(1) = 3 then y(1/2) = ?

I have attached an image of the question with the possible solutions:


Homework Equations





The Attempt at a Solution



Initially I tried plugging in t=1 and y(1) = 3 giving me:

y'(1)+3ln(1) = 0

Hence y'(1) = 0

I did the same for t=1/2

1/2[y'(1/2) + ln(1/2)y(1/2)] = 0

But this doesn't seem to help me. Any suggestions would be appreciated.
 

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Why don't you just solve the DE and put in the boundary conditions? It looks to be separable and linear so you have a couple of options.
 
Northbysouth said:

Homework Statement


If y satisfies the differential equation:

ty'(t) + tln(t)y(t) = 0

and y(1) = 3 then y(1/2) = ?

I have attached an image of the question with the possible solutions:

Homework Equations



The Attempt at a Solution



Initially I tried plugging in t=1 and y(1) = 3 giving me:

y'(1)+3ln(1) = 0

Hence y'(1) = 0

I did the same for t=1/2

1/2[y'(1/2) + ln(1/2)y(1/2)] = 0

But this doesn't seem to help me. Any suggestions would be appreciated.
To help you solve the D.E., factor out t .
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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