- #1
fluidistic
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Homework Statement
I must solve the following diff. eq. ##tx''-(4t+1)x'+(4t+2)x=0## with the initial condition ##x(0)=0## and the relations ##\mathcal {L }[tx]=-\frac{d \mathcal{L}[x]}{ds}##, ##\mathcal {L} [tx']=-\frac{d [s \mathcal {L}[x]]}{ds}## and ##\mathcal{L}[x']=s \mathcal {L}[x]-x(0)##. Where x is a function of t.
Homework Equations
Already given.
The Attempt at a Solution
Well I've calculated ##\mathcal {L}[x''t]## which gave me ##-s^2 \frac{d \mathcal {L}[x]}{ds}-2s \mathcal {L}[x]##.
Then I used the linearity of the Laplace transform and I applied the Laplace transform over the equation. Which eventually lead me to ##-\frac{d(\mathcal{L}[x])}{ds} \cdot s^2 + \mathcal{L}[x] (2-3s)=0##.
This is where I was stuck when starting to write this thread. Because I'm used to obtain an algebraic expression for ##\mathcal {L}[x]##, not a differential equation. I just solved it and reached ##\mathcal{L}[x]=\frac{1}{s^3e^{\frac{2}{s}}}##. Is this the way to go? To finish, I should take the inverse Laplace transform of that.