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D( z )
z^2 = 0
z = 0
z^2 = 0
z^2 = 0
1*z^2 = 0 // : 1
z^2 = 0
z = 0
z = 0
z = 0
z in (-oo:0) U (0:+oo)
1/z+1/z-4+4 = 8/(z^2)-16 // - 8/(z^2)-16
1/z+1/z-(8/(z^2))-4+4+16 = 0
1/z+1/z-8*z^-2-4+4+16 = 0
2*z^-1-8*z^-2+16 = 0
t_1 = z^-1
2*t_1^1-8*t_1^2+16 = 0
2*t_1-8*t_1^2+16 = 0
DELTA = 2^2-(-8*4*16)
DELTA = 516
DELTA > 0
t_1 = (516^(1/2)-2)/(-8*2) or t_1 = (-516^(1/2)-2)/(-8*2)
t_1 = (2*129^(1/2)-2)/(-16) or t_1 = (-2*129^(1/2)-2)/(-16)
t_1 = (2*129^(1/2)-2)/(-16)
z^-1-((2*129^(1/2)-2)/(-16)) = 0
1*z^-1 = (2*129^(1/2)-2)/(-16) // : 1
z^-1 = (2*129^(1/2)-2)/(-16)
-1 < 0
1/(z^1) = (2*129^(1/2)-2)/(-16) // * z^1
1 = ((2*129^(1/2)-2)/(-16))*z^1 // : (2*129^(1/2)-2)/(-16)
-16*(2*129^(1/2)-2)^-1 = z^1
z = -16*(2*129^(1/2)-2)^-1
t_1 = (-2*129^(1/2)-2)/(-16)
z^-1-((-2*129^(1/2)-2)/(-16)) = 0
1*z^-1 = (-2*129^(1/2)-2)/(-16) // : 1
z^-1 = (-2*129^(1/2)-2)/(-16)
-1 < 0
1/(z^1) = (-2*129^(1/2)-2)/(-16) // * z^1
1 = ((-2*129^(1/2)-2)/(-16))*z^1 // : (-2*129^(1/2)-2)/(-16)
-16*(-2*129^(1/2)-2)^-1 = z^1
z = -16*(-2*129^(1/2)-2)^-1
z in { -16*(2*129^(1/2)-2)^-1, -16*(-2*129^(1/2)-2)^-1 }
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