Integrating 1/(x - sqrt(1-x^2))

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Homework Statement


[itex]\int[/itex][itex]\frac{dx}{x-\sqrt{1-x^2}}[/itex]


Homework Equations



The Attempt at a Solution



i try to simplify it by multiplying [itex]\frac{x+\sqrt{1-x^2}}{x+\sqrt{1-x^2}}[/itex],becoming =[itex]\frac{x+\sqrt{1-x^2}}{2x^2-1}[/itex]
=[itex]\int[/itex]{[itex]\frac{x}{2x^2-1}[/itex]+[itex]\frac{\sqrt{1-x^2}}{2x^2-1}[/itex]}dx

ps:
a.Can i partial fraction the last term to [itex]\frac{A}{x-\frac{1}{\sqrt{2}}}[/itex]+[itex]\frac{B}{x+\frac{1}{\sqrt{2}}}[/itex]??
b.i try to integrate by using wolfram alpha online ,but the steps is incredibly long..
does it exist any other simpler way??
 

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I checked W-A, and they did it the same way I would have: Begin with a trig substitution like x=sin(u), then use the Weierstrass substitution: v=tan(u/2). It will be long and difficult, but it's possible.
 
haleycomet2 said:
a.Can i partial fraction the last term to [itex]\frac{A}{x-\frac{1}{\sqrt{2}}}[/itex]+[itex]\frac{B}{x+\frac{1}{\sqrt{2}}}[/itex]??
No, because both the numerator and denominator of the original fraction must be polynomials, and in
[tex]\frac{\sqrt{1-x^2}}{2x^2-1}[/tex]
the numerator is not a polynomial.
 
o,i see.Thanks a lot:smile: