Example 12.16.  Solve the initial value problem  

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Explore Solution 12.16.

Enter the initial conditions and the functions f[t] and F[s].  Then Laplace transform the D.E. and solve for Y[s].

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Using the known Laplace transforms  [Graphics:../Images/LaplaceDiffIntegrateMod_gr_118.gif] the solution f[t] is the linear combination  [Graphics:../Images/LaplaceDiffIntegrateMod_gr_119.gif].  

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Aside. We can check this with Mathematica's  result using the LaplaceTransform package.

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Aside. We can substitute y[t] into the D.E. and verify it is a solution.

[Graphics:../Images/LaplaceDiffIntegrateMod_gr_124.gif]





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Aside. We use Mathematica/s DSolve package to solve the D.E. and plot the solution.

[Graphics:../Images/LaplaceDiffIntegrateMod_gr_126.gif]





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[Graphics:../Images/LaplaceDiffIntegrateMod_gr_129.gif]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(c) 2006 John H. Mathews, Russell W. Howell