Question

\(log_5\left(\dfrac{1}{25}\right).log_{27}9=?\)

\(log_24.log_{\dfrac{1}{4}}2=?\)

a.c giúp em với ạ

thank trước ạ

Answer 1

log\(_5\)(\(\dfrac{1}{25}=log_5\left(5^{-2}\right)=-2\)

log\(_{27}9\)=log\(_{3^3}3^2\)=\(\dfrac{2}{3}\)

\(\Rightarrow\) log\(_5\dfrac{1}{25}\).\(log_{27}9\)=\(\dfrac{-4}{3}\)

Answer 2

\(log_24=log_22^2=2\)

\(log_{\dfrac{1}{4}}2=log_{2^{-2}}2=\dfrac{-1}{2}\)

\(\Rightarrow log_24.log_{\dfrac{1}{4}}2=-1\)