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5*x^2-(((4*x)/3)*x^3) = 0
(-4/3)*x^4+5*x^2 = 0
5*x^2-4/3*x^4 = 0
t_1 = x^2
5*t_1^1-4/3*t_1^2 = 0
5*t_1-4/3*t_1^2 = 0
DELTA = 5^2-(-4/3*0*4)
DELTA = 25
DELTA > 0
t_1 = (25^(1/2)-5)/(-4/3*2) or t_1 = (-25^(1/2)-5)/(-4/3*2)
t_1 = 0 or t_1 = 15/4
t_1 = 0
x^2+0 = 0
x^2 = 0
1*x^2 = 0 // : 1
x^2 = 0
x = 0
t_1 = 15/4
x^2-15/4 = 0
1*x^2 = 15/4 // : 1
x^2 = 15/4
x^2 = 15/4 // ^ 1/2
abs(x) = (15/4)^(1/2)
x = (15/4)^(1/2) or x = -(15/4)^(1/2)
x in { 0, (15/4)^(1/2), -(15/4)^(1/2) }
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