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D( x )
2*x+1 = 0
2*x+1 = 0
2*x+1 = 0
2*x+1 = 0 // - 1
2*x = -1 // : 2
x = -1/2
x in (-oo:-1/2) U (-1/2:+oo)
(x*(1-(2*x)))/(2*x+1) = 0.12 // - 0.12
(x*(1-(2*x)))/(2*x+1)-0.12 = 0
(x*(1-2*x))/(2*x+1)-0.12 = 0
(x*(1-2*x))/(2*x+1)+(-0.12*(2*x+1))/(2*x+1) = 0
x*(1-2*x)-0.12*(2*x+1) = 0
0.76*x-2*x^2-0.12 = 0
0.76*x-2*x^2-0.12 = 0
0.76*x-2*x^2-0.12 = 0
DELTA = 0.76^2-(-2*(-0.12)*4)
DELTA = 0.76^2-0.96
DELTA = -0.3824
DELTA < 0
1 = 0
1/(2*x+1) = 0
1/(2*x+1) = 0 // * 2*x+1
1 = 0
x belongs to the empty set
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