How can I solve this tricky integral involving a radical and trig substitution?

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The integral in question is ∫ (x/√(3-x^4)) dx, which appears to require a trigonometric substitution. A suggestion is to rewrite the expression as (x^2)^2, potentially leading to an incomplete beta function. A hint provided indicates using the substitution u = x^2, simplifying the integral without needing trigonometric methods. The discussion emphasizes finding a starting point rather than a complete solution. The problem is solvable with the right approach, and further clarification is welcomed if needed.
krusty the clown
\int \frac {x}{\sqrt{3-x^4}}\mbox{dx}

Basically I haven't had any luck with anything I have tried. It almost looks like a trig substitution, but I don't know how to deal with the x^4 under the radical. Also, I would rather have a hint as to where to start rather than have the whole problem done for me.


-Thanks, Erik
 
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Deal it as (x^2)^2
 
I think that's going to turn into an incomplete beta function.
 
Tide said:
I think that's going to turn into an incomplete beta function.

I'm not sure what this means, but this problem is from calc II, and the text specifically says there are answers to all of the questions from the section this was taken from.

Cylclovenom said:
Deal it as (x^2)^2

Thanks. I am prety sure I can do this with trig substituion now, but if I can't I will let you know.


-Thanks, Erik
 
Right! I didn't look at it long enough. It's going to be an arcsin with an x^2 in the argument.
 
Read Tide's post he gave it away :smile:
No need for trigonometric substitution.

Hint!
u = x^2
\frac{du}{2}= xdx
 
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