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D( x )
3*x^2-12 = 0
3*x^2-12 = 0
3*x^2-12 = 0
3*x^2 = 12 // : 3
x^2 = 4
x^2 = 4 // ^ 1/2
abs(x) = 2
x = 2 or x = -2
x in (-oo:-2) U (-2:2) U (2:+oo)
(2*x^3-(3*x^2)-(18*x)-8)/(3*x^2-12) = 0
(2*x^3-3*x^2-18*x-8)/(3*x^2-12) = 0
2*x^3-3*x^2-18*x-8 = 0
2*x^3-3*x^2-18*x-8 = 0
{ 1, -1, 2, -2, 4, -4, 8, -8 }
1
x = 1
2*x^3-3*x^2-18*x-8 = -27
1
-1
x = -1
2*x^3-3*x^2-18*x-8 = 5
-1
2
x = 2
2*x^3-3*x^2-18*x-8 = -40
2
-2
x = -2
2*x^3-3*x^2-18*x-8 = 0
-2
x+2
2*x^2-7*x-4
2*x^3-3*x^2-18*x-8
x+2
-2*x^3-4*x^2
-7*x^2-18*x-8
7*x^2+14*x
-4*x-8
4*x+8
0
2*x^2-7*x-4 = 0
DELTA = (-7)^2-(-4*2*4)
DELTA = 81
DELTA > 0
x = (81^(1/2)+7)/(2*2) or x = (7-81^(1/2))/(2*2)
x = 4 or x = -1/2
x in { -1/2, 4, -2}
(x+1/2)*(x-4)*(x+2) = 0
((x+1/2)*(x-4)*(x+2))/(3*x^2-12) = 0
( x+1/2 )
x+1/2 = 0 // - 1/2
x = -1/2
( x+2 )
x+2 = 0 // - 2
x = -2
( x-4 )
x-4 = 0 // + 4
x = 4
x in { -2}
x in { -1/2, 4 }
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