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D( x )
4-x^2 = 0
4-x^2 = 0
4-x^2 = 0
-1*x^2 = -4 // : -1
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)
(8*x-(2*x^3))/(4-x^2) = (2/3)*x // - (2/3)*x
(8*x-(2*x^3))/(4-x^2)-((2/3)*x) = 0
(8*x-2*x^3)/(4-x^2)+(-2/3)*x = 0
(8*x-2*x^3)/(4-x^2)+(-2*x)/3 = 0
(3*(8*x-2*x^3))/(3*(4-x^2))+(-2*x*(4-x^2))/(3*(4-x^2)) = 0
3*(8*x-2*x^3)-2*x*(4-x^2) = 0
16*x-4*x^3 = 0
16*x-4*x^3 = 0
4*x*(4-x^2) = 0
-1*x^2 = -4 // : -1
x^2 = 4
x^2 = 4 // ^ 1/2
abs(x) = 2
x = 2 or x = -2
4*x*(x-2)*(x+2) = 0
(4*x*(x-2)*(x+2))/(3*(4-x^2)) = 0
(4*x*(x-2)*(x+2))/(3*(4-x^2)) = 0 // * 3*(4-x^2)
4*x*(x-2)*(x+2) = 0
( 4*x )
4*x = 0 // : 4
x = 0
( x+2 )
x+2 = 0 // - 2
x = -2
( x-2 )
x-2 = 0 // + 2
x = 2
x in { -2}
x in { 2}
x = 0
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