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D( x )
x^2-(3*x)+9 = 0
x^3+27 = 0
x+3 = 0
x^2-(3*x)+9 = 0
x^2-(3*x)+9 = 0
x^2-3*x+9 = 0
x^2-3*x+9 = 0
DELTA = (-3)^2-(1*4*9)
DELTA = -27
DELTA < 0
x^3+27 = 0
x^3+27 = 0
1*x^3 = -27 // : 1
x^3 = -27
x^3 = -27 // ^ 1/3
x = -3
x+3 = 0
x+3 = 0
x+3 = 0 // - 3
x = -3
x in (-oo:-3) U (-3:+oo)
90/(x^2-(3*x)+9)-((5*x)/(x+3))-(405/(x^3+27)) = 0
90/(x^2-3*x+9)-5*x*(x+3)^-1-405*(x^3+27)^-1 = 0
90/(x^2-3*x+9)+(-5*x)/(x+3)-405/(x^3+27) = 0
x^2-3*x+9 = 0
x^2-3*x+9 = 0
x^2-3*x+9 = 0
DELTA = (-3)^2-(1*4*9)
DELTA = -27
DELTA < 0
1 = 0
(-5*x)/(x+3)-405/(x^3+27)+90 = 0
(90*(x+3)*(x^3+27))/((x+3)*(x^3+27))+(-5*x*(x^3+27))/((x+3)*(x^3+27))+(-405*(x+3))/((x+3)*(x^3+27)) = 0
90*(x+3)*(x^3+27)-5*x*(x^3+27)-405*(x+3) = 0
85*x^4+270*x^3+2295*x-405*x-1215+7290 = 0
85*x^4+270*x^3+1890*x+6075 = 0
85*x^4+270*x^3+1890*x+6075 = 0
5*(17*x^4+54*x^3+378*x+1215) = 0
17*x^4+54*x^3+378*x+1215 = 0
{ 1, -1, 3, -3, 5, -5, 9, -9, 15, -15, 27, -27, 45, -45, 81, -81, 135, -135, 243, -243, 405, -405, 1215, -1215 }
1
x = 1
17*x^4+54*x^3+378*x+1215 = 1664
1
-1
x = -1
17*x^4+54*x^3+378*x+1215 = 800
-1
3
x = 3
17*x^4+54*x^3+378*x+1215 = 5184
3
-3
x = -3
17*x^4+54*x^3+378*x+1215 = 0
-3
x+3
17*x^3+3*x^2-9*x+405
17*x^4+54*x^3+378*x+1215
x+3
-17*x^4-51*x^3
3*x^3+378*x+1215
-3*x^3-9*x^2
378*x-9*x^2+1215
9*x^2+27*x
405*x+1215
-405*x-1215
0
17*x^3+3*x^2-9*x+405 = 0
{ 1, -1, 3, -3, 5, -5, 9, -9, 15, -15, 27, -27, 45, -45, 81, -81, 135, -135, 405, -405 }
1
x = 1
17*x^3+3*x^2-9*x+405 = 416
1
-1
x = -1
17*x^3+3*x^2-9*x+405 = 400
-1
3
x = 3
17*x^3+3*x^2-9*x+405 = 864
3
-3
x = -3
17*x^3+3*x^2-9*x+405 = 0
-3
x+3
17*x^2-48*x+135
17*x^3+3*x^2-9*x+405
x+3
-17*x^3-51*x^2
405-48*x^2-9*x
48*x^2+144*x
135*x+405
-135*x-405
0
17*x^2-48*x+135 = 0
DELTA = (-48)^2-(4*17*135)
DELTA = -6876
DELTA < 0
x in { -3, -3}
5*(x+3)^2 = 0
(5*(x+3)^2)/((x+3)*(x^3+27)) = 0
(5*(x+3)^2)/((x+3)*(x^3+27)) = 0 // * (x+3)*(x^3+27)
5*(x+3)^2 = 0
x+3 = 0 // - 3
x = -3
x in { -3}
x belongs to the empty set
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