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Evaluate the integral \int \frac{x}{(x^2 - 4) \sqrt{x^4 - 8x^2}} \, dx
by making the substitution u = x^{2}
\int \frac{1}{(x^2 - 4) \sqrt{x^4 - 8x^2}} \, xdx\frac{1}{2} \int \frac{1}{(u) \sqrt{x^4 - 8x^2}} \, du\frac{1}{2} \int \frac{1}{(u)} \frac{1}{\sqrt{x^4 - 8x^2}} \, du
\frac{1}{2} \int \frac{1}{(u)} \frac{1}{|x|\sqrt{x^2 - 8}} \, duI haven't yet committed all of the inverse trig functions to memory but I have a table that shows dy/dsec^{-1}(x) = \frac{1}{|x| \sqrt{x^2 - 1}}
However, I do not know how to handle \frac{1}{|x| \sqrt{x^2 - 8}}
What does that equal and why? I mean what is the relationship between it and whatever it's antiderivative may be?
by making the substitution u = x^{2}
Homework Equations
The Attempt at a Solution
u = x^{2} - 4 so \frac{du}{2}= xdx\int \frac{1}{(x^2 - 4) \sqrt{x^4 - 8x^2}} \, xdx\frac{1}{2} \int \frac{1}{(u) \sqrt{x^4 - 8x^2}} \, du\frac{1}{2} \int \frac{1}{(u)} \frac{1}{\sqrt{x^4 - 8x^2}} \, du
\frac{1}{2} \int \frac{1}{(u)} \frac{1}{|x|\sqrt{x^2 - 8}} \, duI haven't yet committed all of the inverse trig functions to memory but I have a table that shows dy/dsec^{-1}(x) = \frac{1}{|x| \sqrt{x^2 - 1}}
However, I do not know how to handle \frac{1}{|x| \sqrt{x^2 - 8}}
What does that equal and why? I mean what is the relationship between it and whatever it's antiderivative may be?
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