[tex]2lg^2x^3-3lgx-1=0[/tex]
[tex]2(lgx^3)^2-3lgx-1=0[/tex]
[tex]2(3lgx)^2-3lgx-1=0[/tex]
[tex]2*9lg^2x-3lgx-1=0[/tex]; Notam lg x cu a
[tex]18a^2-3a-1 = 0 [/tex]
[tex]a_1 = \frac{1}{3} [/tex]
[tex]a_2 = \frac{-1}{6} [/tex]
[tex]lg x = \frac{1}{3} [/tex] => x = [tex] \sqrt[3]{10} [/tex]
[tex]lg x = \frac{-1}{6} [/tex] => x = [tex] \frac{1}{ \sqrt[6]{10} } [/tex]
