Area between curves

intervade

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Apr 6, 2009
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Ok, I'm given y = x-x^2 ( or y = -(x-1)^2+1 ). Now I'm also told that there is a line that passes through the origin that divides that area between that curve and the x-axis into 2 equal regions. I'm asked to find the slope of the line.

Just checking my work here.. basically I get down to solving for the point of intersection of y=mx and y=x-x^2, so I set them equal, and x = 1-m. Now I setup an integral from 0 to 1-m of [(x-x^2)-(mx)]dx = 1/12 and I Get something like this...

[(x^2)/2 - (x^3)/3 - (mx^2)/2| from 0 to 1-m = 1/12, and I plug in 1-m for x. I end up down to 1-3m+9m^2+6m^3 = 1/12.. I may have messed up on my algebra or the idea all together, but I cant seem to find a correct value. When I solve that equation, I Get a negative number.. (-1.82....) and I am pretty sure that's not correct. I assume I integrate m as a constant? Help would be much appreciated!
 
\(\displaystyle First \ of \ all, \ x-x^{2} \ \ne \ -(x-1)^{2}+1\)

\(\displaystyle Second, \ see \ lamaclass's \ thread \ below \ (area \ under \ curve) \ and \ then \ see \ BGtH's \ solution.\)
 
Ha! I apologize, I did correct that error(which was one of the many errors I had made) but needless to say, I was on the right track and found my slope! Thanks ;)
 
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