Giải các phương trình mũ sau:
a) $3^{x+1}=2$
b) $3^{2x^2+5x+4}=9$
c) $2^x=\frac{1}{8}$
a) ${\left(\frac{1}{7}\right)}^{x^2-2x-3}=7^{x+1}$
b) $4^{5x-2}=64$
g) $3^{x^2-4}={\left(\frac{1}{9}\right)}^{3x-1}$
g) $\log x+\log \left(x-9\right)=1$ h) ${\log }_3\left({\log }_{2}a\right)=0$
i) $\left(x^2-2x-3\right){\log }_{2}x=0$ k) $\left(x^2+2x-3\right)\left({\log }_{2}x-3\right)=0$
g) ${\log }_2\left(x+1\right)-2{\log }_{\frac{1}{4}}\left(x-1\right)=3$ h) ${\log }_3\left(6+x\right)+{\log }_3\left(9x\right)-5=0$
i) ${\log }_{2}x+{\log }_{3}x=1+{\log }_{2}x{\log }_{3}x$ k) ${\log }_3\left(9^x-5.3^x+7\right)=x+1$
l) ${\log }_{3}x.{\log }_{9}x.{\log }_{27}x.{\log }_{81}x=\frac{2}{3}$