MHB -2.4.2 interval of initial value problem

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The discussion focuses on determining the interval for the solution of the initial value problem defined by the differential equation $t(t-4)y' + y = 0$ with the condition $y(2) = 2$ for $0 < t < 4$. Participants note that the derivative $y'$ is undefined at the boundaries $t = 0$ and $t = 4$, indicating that solutions cannot exist at these points. The initial condition $y(2) = 2$ confirms that the solution is valid within the interval $0 < t < 4$. The consensus is that the specified interval is appropriate, as it aligns with the problem's constraints and the behavior of the differential equation. Overall, the solution is confirmed to exist in the interval $0 < t < 4$.
karush
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Determine an interval in which the solution of the given initial value problem is certain to exist

$t(t-4)y'+y=0 \quad y(2)=2\quad 0<t<4$

ok my first step was isolate y'
s
$y'=-\dfrac{y}{t(t-4)}$

not sure what direction to go since we are concerned about an interval
 
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Well, the problem specifically says "0< t< 4" and y' does not exist at t= 0 and t= 4.
 
how does y(2)=2 fit into this
doesn't that give us specific y interval
 
karush said:
how does y(2)=2 fit into this
doesn't that give us specific y interval
You could always do "brute force" if you can't figure out a work around. Boundary conditions get rid of integration constants. Solve the differential equation. What is y(t)? What does that tell you about the solution interval(s)?

-Dan
 
IF the "0< t< 4" were not there you would still be able to observe that if x= 0 or x= 4, the denominator would be 0 so y' would not exist. That would tell you that a solution cannot be extended across x= 0 or x= 4. But you could have solutions for x< 0 or x> 4. The fact that you are given y at x= 2, which is between 0 and 2 tells you that the correct interval is 0< x< 4, not x< 0 or x> 4. But, as I said, that is redundant since the problem itself says "0< x< 4".
 

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