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D( x )
x = 0
x = 0
x = 0
x in (-oo:0) U (0:+oo)
3/x = (15/8)*x+3 // - (15/8)*x+3
3/x-((15/8)*x)-3 = 0
(-15/8)*x+3/x-3 = 0
3*x^-1-15/8*x^1-3*x^0 = 0
(3*x^0-15/8*x^2-3*x^1)/(x^1) = 0 // * x^2
x^1*(3*x^0-15/8*x^2-3*x^1) = 0
x^1
(-15/8)*x^2-3*x+3 = 0
(-15/8)*x^2-3*x+3 = 0
DELTA = (-3)^2-(3*4*(-15/8))
DELTA = 63/2
DELTA > 0
x = ((63/2)^(1/2)+3)/(2*(-15/8)) or x = (3-(63/2)^(1/2))/(2*(-15/8))
x = -4/15*((63/2)^(1/2)+3) or x = -4/15*(3-(63/2)^(1/2))
x in { -4/15*((63/2)^(1/2)+3), -4/15*(3-(63/2)^(1/2))}
x in { -4/15*((63/2)^(1/2)+3), -4/15*(3-(63/2)^(1/2)) }
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