Question

calcule o valor de 5⁻¹+5⁻²
                          5⁻³

Answer 1

1/5 + 1/25 + 1\125
25\125 + 5\125+1/125 =31\125

Answer 2

$\frac{5^-^1+5^-^2}{5^-^3} = \frac{ \frac{1}{5} +( \frac{1}{5})^2 }{( \frac{1}{5})^3 } =$

$\frac{ \frac{1}{5} + \frac{1}{25} }{ \frac{1}{125} } =---> mmc(5,25) = 25$

$\frac{ \frac{5}{25} + \frac{1}{25} }{ \frac{1}{125} } = \frac{ \frac{6}{25} }{ \frac{1}{125} } =$

$\frac{6}{25} : \frac{1}{125} = \frac{6}{25} . \frac{125}{1} = \frac{750}{25} = 30$