Matematika..dari semalam gak ada yang bisa jawab..tolong dong yang bisa.

[tex]^6\log{12}+^6\log{9}-^6\log{3}=^6\log{\frac{12\times 9}{3}}\\=^6\log{36}\\=2[/tex]

[tex]^2\log{3}\times ^3\log{5}=ab\\^2\log{5}=ab\\^5\log{2}=\frac{1}{ab}\\2\times ^5\log{2}=2\times\frac{1}{ab}\\^5\log{4}=\frac{2}{ab}\\\\ ^{12}\log{60}=^{12}\log{12}+^{12}\log{5}\\=1+\frac{1}{^5\log{12}}\\=1+\frac{1}{^5\log{4}+^5\log{3}}\\=1+\frac{1}{\frac{2}{ab}+\frac{1}{b}}\\=1+\frac{1}{\frac{2+a}{ab}}\\=1+\frac{ab}{2+a}\\=\frac{ab+a+2}{a+2}[/tex]

[tex]^5\log{3}\times ^3\log{2}=ab\\^5\log{2}=ab\\^2\log{5}=\frac{1}{ab}\\\\^{20}\log{54}=^{20}\log{3^3}+^{20}\log{2}\\=3\times ^{20}\log{3}+\frac{1}{^2\log{20}}\\=\frac{3}{^3\log{20}}+\frac{1}{^2\log{5}+^2\log{4}}\\=\frac{3}{^3\log{4}+^3\log{5}}+\frac{1}{\frac{1}{ab}+2}\\=\frac{3}{2a+\frac{1}{b}}+\frac{1}{\frac{1+2ab}{ab}}\\=\frac{3}{\frac{2ab+1}{b}}+\frac{ab}{2ab+1}\\=\frac{3b+ab}{2ab+1}[/tex]