Question

calcule as potências.
a) 3 -¹ (3 elevado a -1)

b)( 1 ) -³
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5 ​

Answer 1

Explicação passo-a-passo:

Lembre-se que:

$\sf a^{-n}=\dfrac{1}{a^n}$

a)

$\sf 3^{-1}=\dfrac{1}{3^1}$

$\sf \red{3^{-1}=\dfrac{1}{3}}$

b)

$\sf \Big(\dfrac{1}{5}\Big)^{-3}=5^3$

$\sf \Big(\dfrac{1}{5}\Big)^{-3}=5\cdot5\cdot5$

$\sf \Big(\dfrac{1}{5}\Big)^{-3}=25\cdot5$

$\sf \red{\Big(\dfrac{1}{5}\Big)^{-3}=125}$