Question

Calcule:
7-²

($\frac{5}{7}$) -²
( $\frac{2}{5}$) -³
( $\frac{2}{3}$ ) elevado a 4
5-³
( $\frac{6}{3}$ ) -¹

Answer 1

Para retirar o sinal de negativo dos expoentes transforme em fração:

$7^-^2 => \ \ (\dfrac{1}{7})^2 \ \ => \dfrac{1}{49}$

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Inverta a fração e retire o sinal de negativo

$(\dfrac{5}{7})^-^2 \ \ => (\dfrac{7}{5})^2 \ \ => \dfrac{49}{25}$

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$(\dfrac{2}{5})^-^3 \ \ => \dfrac{5}{2}^3 \ \ => \ \ \dfrac{125}{8}$

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$(\dfrac{2}{3})^4 \ \ => \dfrac{16}{81}$

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$5^-^3 \ \ => \ \ (\dfrac{1}{5})^3 \ \ => \ \ \dfrac{1}{125}$

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$(\dfrac{6}{3})^-^1 \ \ => \ \ (\dfrac{3}{6})^1 \ \ => \dfrac{3}{6} => \dfrac{1}{2}$