Question

Exercícios:

Determine o valor de:

(exercícios na imagem)​

Answer 1

$\boxed{\begin{array}{l}\underline{\rm D\!~efinic_{\!\!,}\tilde ao~de~logaritmo}\\\sf \ell og_ba=x\Longleftrightarrow\begin{cases}\sf a>0\\\sf b>0\\\sf b\ne1\end{cases}\\\tt a)~\sf\ell og_4x=2\\\sf x=4^2\\\sf x=16\\\tt b)~\sf\ell og_3x=-2\\\sf x=3^{-2}\\\sf x=\bigg(\dfrac{1}{3}\bigg)^2\\\sf x=\dfrac{1}{9}\\\tt c)~\sf\ell o_28= x\\\sf 2^x=8\\\sf 2^x=2^3\\\sf x=3\\\tt d)~\sf\ell og_327=x\\\sf 3^x=27\\\sf 3^x=3^3\\\sf x=3\\\tt e)~\sf\ell og_x128=7\\\sf x^7=128\\\sf x=\sqrt[\sf7]{\sf128}\\\sf x=\sqrt[\sf\backslash\!\!\!7]{\sf2^{\backslash\!\!\!7}}\\\sf x=2\\\tt f)~\sf\ell og_x125=3\\\sf x^3=125\\\sf x=\sqrt[\sf3]{\sf125}\\\sf x=\sqrt[\sf\backslash\!\!\!3]{\sf5^{\backslash\!\!\!3}}\\\sf x=5\end{array}}$