Question

resolva as equações :
a)log5 x=2
b)logx 243=5
c)logx 1/9 =2

Answer 1

$log_{5}(x)=2 \\ x=5^{2} \\ \\ \\ log_{x}(243)=5 \\ 243=x^{5} \\ 3^{5}=x^{5} \\ x=3 \\ \\ \\ log_{x}(\frac{1}{9})=2 \\ \frac{1}{9}=x^{2} \\ \frac{1^{2}}{3^{2}}=x^{2} \\ (\frac{1}{3})^{2}=x^{2} \\ x=\frac {1}{3}$