Question

Calcule As potências:

A:
${10}^{ - 1} =$
B:
$( \frac {-1}{3}) { } {}^{ - 1} =$
C:
$( {12}^{ - 2} =$
D:
$( \frac{ + 3}{5}) {}^{ - 3} =$
e:
$( \frac{ - 9}{4} ) {}^{ - 2} =$
HELP PLEASE


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Answer 1

Olá, tudo bem? Todas suas questões tratam de valores numéricos elevados a expoente negativo, veja:

$\text{A:}\,\,\boldsymbol{10^{-1}=\dfrac{1}{10^1}=\dfrac{1}{10}\,\,\checkmark}$

 $\text{B:}\,\,\boldsymbol{\left(-\dfrac{1}{3}\right)^{-1}=\dfrac{1}{\left(-\dfrac{1}{3}\right)}=-3\,\,\checkmark}$

   $\text{C:}\,\,\boldsymbol{12^{-2}=\dfrac{1}{12^2}=\dfrac{1}{144}\,\,\checkmark}$

     $\text{D:}\,\,\boldsymbol{\left(\dfrac{3}{5}\right)^{-3}=\dfrac{1}{\left(\dfrac{3}{5}\right)^3}=\dfrac{1}{\dfrac{27}{125}}=\dfrac{125}{27}\,\,\checkmark}$

       $\text{E:}\,\,\boldsymbol{\left(-\dfrac{9}{4}\right)^{-2}=\dfrac{1}{\left(-\dfrac{9}{4}\right)^2}=\dfrac{1}{\dfrac{81}{16}}=\dfrac{16}{81}\,\,\checkmark}$

É isso!! :)