Solving Arc Length Integral for y=ln(1-x^2) - 0 to 1/2

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hachi_roku
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Homework Statement



ok, the original prob is : find the length of the curve of y=ln(1-x^2) x between 0, 1/2.



Homework Equations





The Attempt at a Solution


ive made it this far: my integral is -1 + 2/1-x^2.....ok so i decompose the second part but in doing so i get a negative to make it -(x+1)(x-1) but i don't know what happens to that negative because the solution manual says the integral is ...-1+ 1/x+1 -1/x-1 dx i don't get the signs. please help!
 
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if we are woking with single variable functions, y=f(x) like here then the arc length from a to be of a curve is:


[tex]L=\int_a^b\sqrt{1+[f'(x)]^2}dx[/tex]
 
yes...like i said I've already worked that part...im toward the end of the problem i just don't get the signs
 
hachi_roku said:
yes...like i said I've already worked that part...im toward the end of the problem i just don't get the signs

Well, since you have shown almost no work(step by step) it is hard to tell where you have missed, or what you are doing wrong.