(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

y' + (2/t)y = cos(t) / t^2 initial cond: y(pi) = 0 .... t>0

2. Relevant equations

integrating factor is t^2

so.. integ (yt^2)' = integ cos (t)

= yt^2 = -sin (t) + c

y = ( -sin (t) /t^2 ) + c

..this brings up my first question.. when i divided through by t^2 to isolate y, am i correct in saying that I dont need to also divide c by t^2, because a constant divided by a constant is still just another constant.. right?

so .. with that assumption...

0 = ( - sin (pi) / pi^2 )+ c

0 = ( - 0 / pi^2 ) + c

0 = c

this where im stuck, because i realize IC said that t>0.. but what does it mean to apply that IC to the equation?? Does this lead to an actual value for c somehow? thanks

edit: if it says that t = pi .. that is, y(pi) = 0 .. then why would it also say t>0 ?? pi is clearly bigger than zero, so why the added condition?

3. The attempt at a solution

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Differential Equation dont understand t>0 how to apply that to equation

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