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64*x^4*y^-8*z^2 < 0
64*x^4*y^-8*z^2 < 0
64*x^4*y^-8*z^2 < 0
64*x^4*y^-8*z^2 = 0
64*x^4*y^-8*z^2 = 0 // : 64*y^-8*z^2
x^4 = 0
x = 0
x < 0
(-oo:0)(0:+oo)x-+
x in <0:+oo)
(64*x^4*y^-8*z^2)^(1/2) = 0
8*x^2*y^-4*z = 0 // : 8*y^-4*z
x^2 = 0
x = 0
x = 0
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