Laplace transform and tabular integration

robertjford80
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Homework Statement



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The Attempt at a Solution



I can't get the jump to [e^-st(-s cost bt + b sin bt)]/(s^2+b^2)

They say they have to use integration by parts but when e and a trig ratio are involved that requires tabular integration. They're obviously not using tabular integration and I don't see why not.
 
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Most classes do not use tabular integration, I've never heard of it. You can use integration by parts (twice, and you must do it correctly (otherwise you will find 0=0)). If you know tabular integration, then you have a technique that many of us do not know.

If you tried the integration by parts, and it did not work, show us your steps and we should be able to give a clue.

Tabular integration is not "required".
 
Never heard the name. It's still integration by parts. Show us the steps if you had trouble integrating.

And I think you only have to integrate twice.
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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