0, \ x \ne 1\\\\
3\lg^2 x = 1 + 2\lg x\\\\
3\lg^2 x - 2\lg x - 1 = 0, \ t = \lg x" alt="x^{3\lg x} = 10x^2\\\\
10 = x^{\log_{x} 10}\\\\
x^{3\lg x} = x^{\log_{x} 10}x^2\\\\
x^{3\lg x} = x^{\log_{x} 10 + 2}\\\\
3\lg x = \log_{x}10 + 2 \ | \ * \lg x, \ x > 0, \ x \ne 1\\\\
3\lg^2 x = 1 + 2\lg x\\\\
3\lg^2 x - 2\lg x - 1 = 0, \ t = \lg x" align="absmiddle" class="latex-formula">