• Matéria: Matemática
  • Autor: pedrospedo
  • Perguntado 8 anos atrás

Mostre que (log_3⁡〖 √243 √81∛3〗)/log_2⁡∜(64 )+log_e⁡e ^(-10) vale -43/102

Respostas

respondido por: viniciushenrique406
0
\textsf{*Essa quest\~ao envolve grande aplica\c{c}\~ao de propriedades exponenciais}\\\textsf{portanto antes de resolver a quest\~ao vou descrever algumas propried\underline{a}}\\\textsf{des exponenciais e logar\'itmicas para que n\~ao ocorram d\'uvidas: }


\large\textsf{Principais propriedades exponenciais:}\\\\\\\mathsf{P1.~~a^m\cdot a^n=a^{m+n}}\\\\\\\mathsf{P2.~~\dfrac{a^m}{a^n}=a^{m-n}~~~~(para~a \neq0~e~m \geq n)}\\\\\\\mathsf{P3.~~(a\cdot b)^n=a^n\cdot b^n}\\\\\\\mathsf{P4.~~(\dfrac{a}{b})^n=\dfrac{a^n}{b^n}~~~~(b \neq 0)}\\\\\\\mathsf{P5.~~(a^m)^n=a^{m\cdot n}}\\\\\\\textsf{Expoente racional:}~~\large\fbox{$\mathsf{a^{\frac{b}{c}}=\sqrt[c]{\mathsf{a^b}}}$}\\\\\\\textsf{Expoente inteiro negativo:}~~\fbox{$\mathsf{a^{-n}=\dfrac{1}{a^n}}$}


\large\textsf{Principais propriedades dos logaritmos:}\\\\\\\mathsf{P1.~~\ell og_a(b\cdot c)=\ell og_a b+\ell og_a c}\\\\\\\mathsf{P2.~~\ell og_a(\dfrac{b}{c})=\ell og_ab-\ell og_ac}\\\\\\\mathsf{P3.~~\ell og_ab^{\alpha}=\alpha\cdot\ell og_ab}\\\\\\\textsf{Mudan\c{c}a~de~base:}~~\fbox{$\mathsf{\ell og_ab=\dfrac{\ell og_ca}{\ell og_cb}}$}


\textsf{Agora vamos para a quest\~ao~~=)}


\mathsf{\dfrac{\ell og_3~\sqrt{243\cdot\sqrt{81\cdot\sqrt[\mathsf{3}]{\mathsf{3}}}}}{\ell og_2\sqrt[4]{64}+\ell og_\mathit{e}\mathit{e}^{-10}}}~\Leftrightarrow~\mathsf{\dfrac{\ell og_3~\sqrt{3^5\cdot\sqrt{9^2\cdot 3^{\frac{1}{3}}}}}{\ell og_2(\sqrt[4]{2^4\cdot4})+(-10\ell og_\mathit{e}\mathit{e})}}


\mathsf{\dfrac{\ell og_3~\sqrt{3^5\cdot(9^2\cdot 3^{\frac{1}{3}})^{\frac{1}{2}}}}{\ell og_2~(2\sqrt[4]{2^2})+(-10\cdot 1)}}~\Leftrightarrow~\mathsf{\dfrac{\ell og_3~\sqrt{3^5\cdot9^{2\cdot\frac{1}{2}}\cdot3^{\frac{1}{3}\cdot\frac{1}{2}}}}{\ell og_2(2^1\cdot(2^2)^{\frac{1}{4}})+(-10)}}


\mathsf{\dfrac{\ell og_3~\sqrt{3^5\cdot9\cdot3^{\frac{1}{6}}}}{\ell og_2(2^1\cdot2^{\frac{2}{4}})-10}}~\Leftrightarrow~\mathsf{\dfrac{\ell og_3~\sqrt{3^5\cdot3^2\cdot3^{\frac{1}{6}}}}{\ell og_2(2^{1+\frac{2}{4}})-10}}~\Leftrightarrow~\mathsf{\dfrac{\ell og_3~3\sqrt{3^5\cdot3^{\frac{1}{6}}}}{\ell og_22^{\frac{3}{2}}-10}}


\mathsf{\dfrac{\ell og_3~(3\sqrt{3^{5+\frac{1}{6}}})}{\frac{3}{2}\ell og_22-10}}~\Leftrightarrow~\mathsf{\dfrac{\ell og_3~(3\sqrt{3^{\frac{31}{6}}})}{(\frac{3}{2}\cdot1)-10}}~\Leftrightarrow~\mathsf{\dfrac{\ell og_3~(3\cdot({3^{\frac{31}{6}}})^{\frac{1}{2}})}{\dfrac{3}{2}-10}}

\mathsf{\dfrac{\ell og_3~(3\cdot({3^{\frac{31}{6}\cdot{\frac{1}{2}}}}))}{-\dfrac{17}{2}}}~\Leftrightarrow~\mathsf{\dfrac{\ell og_3~(3\cdot{3^{\frac{31}{12}}})}{-\dfrac{17}{2}}}~\Leftrightarrow~\mathsf{\dfrac{\ell og_3~({3^{\frac{31}{12}+1}})}{-\dfrac{17}{2}}}~\Leftrightarrow~\mathsf{\dfrac{\ell og_3~{3^{\frac{43}{12}}}}{-\dfrac{17}{2}}}

\mathsf{\dfrac{\frac{43}{12}\ell og_3~{3}}{-\dfrac{17}{2}}}~\Leftrightarrow~\mathsf{\dfrac{\frac{43}{12}\cdot 1}{-\dfrac{17}{2}}}~\Leftrightarrow~\mathsf{\dfrac{\dfrac{43}{12}}{-\dfrac{17}{2}}}~\Leftrightarrow~\mathsf{\dfrac{-86}{204}~\Leftrightarrow~\fbox{$-\dfrac{43}{102}$}~~\checkmark}

viniciushenrique406: nem doeu ;-;
viniciushenrique406: qualquer dúvida pode perguntar...
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