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D( x )
x = 0
x = 0
x = 0
x in (-oo:0) U (0:+oo)
(6*x^2+43*x+39)/x+6 = 0
(6*x^2+43*x+39)/x+(6*x)/x = 0
6*x^2+43*x+6*x+39 = 0
6*x^2+49*x+39 = 0
6*x^2+49*x+39 = 0
6*x^2+49*x+39 = 0
DELTA = 49^2-(4*6*39)
DELTA = 1465
DELTA > 0
x = (1465^(1/2)-49)/(2*6) or x = (-1465^(1/2)-49)/(2*6)
x = (1465^(1/2)-49)/12 or x = (-(1465^(1/2)+49))/12
(x+(1465^(1/2)+49)/12)*(x-((1465^(1/2)-49)/12)) = 0
((x+(1465^(1/2)+49)/12)*(x-((1465^(1/2)-49)/12)))/x = 0
((x+(1465^(1/2)+49)/12)*(x-((1465^(1/2)-49)/12)))/x = 0 // * x
(x+(1465^(1/2)+49)/12)*(x-((1465^(1/2)-49)/12)) = 0
( x+(1465^(1/2)+49)/12 )
x+(1465^(1/2)+49)/12 = 0 // - (1465^(1/2)+49)/12
x = -((1465^(1/2)+49)/12)
( x-((1465^(1/2)-49)/12) )
x-((1465^(1/2)-49)/12) = 0 // + (1465^(1/2)-49)/12
x = (1465^(1/2)-49)/12
x in { -((1465^(1/2)+49)/12), (1465^(1/2)-49)/12 }
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