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D( x )
x = 0
x = 0
x = 0
x in (-oo:0) U (0:+oo)
(9*x+3)/x = 8*x-4 // - 8*x-4
(9*x+3)/x-(8*x)+4 = 0
(9*x+3)/x-8*x+4 = 0
(9*x+3)/x+(-8*x*x)/x+(4*x)/x = 0
9*x-8*x*x+4*x+3 = 0
9*x-8*x^2+4*x+3 = 0
13*x-8*x^2+3 = 0
13*x-8*x^2+3 = 0
13*x-8*x^2+3 = 0
DELTA = 13^2-(-8*3*4)
DELTA = 265
DELTA > 0
x = (265^(1/2)-13)/(-8*2) or x = (-265^(1/2)-13)/(-8*2)
x = (265^(1/2)-13)/(-16) or x = (265^(1/2)+13)/16
(x-((265^(1/2)-13)/(-16)))*(x-((265^(1/2)+13)/16)) = 0
((x-((265^(1/2)-13)/(-16)))*(x-((265^(1/2)+13)/16)))/x = 0
((x-((265^(1/2)-13)/(-16)))*(x-((265^(1/2)+13)/16)))/x = 0 // * x
(x-((265^(1/2)-13)/(-16)))*(x-((265^(1/2)+13)/16)) = 0
( x-((265^(1/2)+13)/16) )
x-((265^(1/2)+13)/16) = 0 // + (265^(1/2)+13)/16
x = (265^(1/2)+13)/16
( x-((265^(1/2)-13)/(-16)) )
x-((265^(1/2)-13)/(-16)) = 0 // + (265^(1/2)-13)/(-16)
x = (265^(1/2)-13)/(-16)
x in { (265^(1/2)+13)/16, (265^(1/2)-13)/(-16) }
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