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D( x )
7*x^2-(3*x^4) = 0
7*x^2-(3*x^4) = 0
7*x^2-(3*x^4) = 0
7*x^2-3*x^4 = 0
t_1 = x^2
7*t_1^1-3*t_1^2 = 0
7*t_1-3*t_1^2 = 0
DELTA = 7^2-(-3*0*4)
DELTA = 49
DELTA > 0
t_1 = (49^(1/2)-7)/(-3*2) or t_1 = (-49^(1/2)-7)/(-3*2)
t_1 = 0 or t_1 = 7/3
t_1 = 0
x^2+0 = 0
x^2 = 0
1*x^2 = 0 // : 1
x^2 = 0
x = 0
t_1 = 7/3
x^2-7/3 = 0
1*x^2 = 7/3 // : 1
x^2 = 7/3
x^2 = 7/3 // ^ 1/2
abs(x) = (7/3)^(1/2)
x = (7/3)^(1/2) or x = -(7/3)^(1/2)
x in (-oo:-(7/3)^(1/2)) U (-(7/3)^(1/2):0) U (0:(7/3)^(1/2)) U ((7/3)^(1/2):+oo)
(x^2)/(7*x^2-(3*x^4)) = 0
(x^2)/(7*x^2-3*x^4) = 0
7*x^2-3*x^4 = 0
x^2*(7-3*x^2) = 0
-3*x^2 = -7 // : -3
x^2 = 7/3
x^2 = 7/3 // ^ 1/2
abs(x) = (7/3)^(1/2)
x = (7/3)^(1/2) or x = -(7/3)^(1/2)
x^2*(x-(7/3)^(1/2))*(x+(7/3)^(1/2)) = 0
(x^2)/(x^2*(x-(7/3)^(1/2))*(x+(7/3)^(1/2))) = 0
1*x^2 = 0 // : 1
x^2 = 0
x = 0
x in { 0}
x belongs to the empty set
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