How do I Integrate \sqrt{1+x^4+2x^2}?

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miglo
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Homework Statement


[tex]y=\frac{1}{3}\left(x^2+2\right)^{3/2}[/tex]


Homework Equations


[tex]\int_{a}^{b}\sqrt{1+\left(\frac{dy}{dx}\right)^{2}}dx[/tex]


The Attempt at a Solution


[tex]\frac{dy}{dx}=x\sqrt{x^2+2}[/tex]
[tex]\int_{0}^{3}\sqrt{1+\left(x\sqrt{x^2+2}\right)^{2}}dx=\int_{0}^{3}\sqrt{1+x^4+2x^2}dx[/tex]
I'm stuck with that integral, not sure what the antiderivative for that function would be
Any hints at the next step would be greatly appreciated.
 
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Here's a hint: x4+2x2+1 = (x2+1)2
 
Wow I can't believe i didn't see that.
I tried Wolfram Alpha earlier and they used a substitution but i couldn't follow their steps so i decided to consult the Physics Forums.
Thanks Char. Limit.