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D( x )
0.5-x = 0
0.5-x = 0
0.5-x = 0
0.5-x = 0 // - 0.5
-x = -0.5 // * -1
x = 0.5
x in (-oo:0.5) U (0.5:+oo)
0.2 = (x^2)/(0.5-x) // - (x^2)/(0.5-x)
0.2-((x^2)/(0.5-x)) = 0
(-1*x^2)/(0.5-x)+0.2 = 0
(-1*x^2)/(0.5-x)+(0.2*(0.5-x))/(0.5-x) = 0
0.2*(0.5-x)-1*x^2 = 0
0.1-x^2-0.2*x = 0
0.1-x^2-0.2*x = 0
0.1-x^2-0.2*x = 0
DELTA = (-0.2)^2-(-1*0.1*4)
DELTA = 0.2^2+0.4
DELTA = 0.44
DELTA > 0
x = ((0.2^2+0.4)^(1/2)+0.2)/(-1*2) or x = (0.2-(0.2^2+0.4)^(1/2))/(-1*2)
x = ((0.2^2+0.4)^(1/2)+0.2)/(-2) or x = (0.2-(0.2^2+0.4)^(1/2))/(-2)
(x-(((0.2^2+0.4)^(1/2)+0.2)/(-2)))*(x-((0.2-(0.2^2+0.4)^(1/2))/(-2))) = 0
((x-(((0.2^2+0.4)^(1/2)+0.2)/(-2)))*(x-((0.2-(0.2^2+0.4)^(1/2))/(-2))))/(0.5-x) = 0
((x-(((0.2^2+0.4)^(1/2)+0.2)/(-2)))*(x-((0.2-(0.2^2+0.4)^(1/2))/(-2))))/(0.5-x) = 0 // * 0.5-x
(x-(((0.2^2+0.4)^(1/2)+0.2)/(-2)))*(x-((0.2-(0.2^2+0.4)^(1/2))/(-2))) = 0
( x-(((0.2^2+0.4)^(1/2)+0.2)/(-2)) )
x-(((0.2^2+0.4)^(1/2)+0.2)/(-2)) = 0 // + ((0.2^2+0.4)^(1/2)+0.2)/(-2)
x = ((0.2^2+0.4)^(1/2)+0.2)/(-2)
( x-((0.2-(0.2^2+0.4)^(1/2))/(-2)) )
x-((0.2-(0.2^2+0.4)^(1/2))/(-2)) = 0 // + (0.2-(0.2^2+0.4)^(1/2))/(-2)
x = (0.2-(0.2^2+0.4)^(1/2))/(-2)
x in { ((0.2^2+0.4)^(1/2)+0.2)/(-2), (0.2-(0.2^2+0.4)^(1/2))/(-2) }
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