Question

calcule: a) 3^2+3^-2

Answer 1

Boa noite!

$3^2\;+\;3^-^2=\\ \\ 9\;+\; \frac{1}{3^2} =\\ \\ 9\;+\; \frac{1}{9} \\ \\ mmc=9\\ \\ \frac{81\;+\;1}{9} = \frac{82}{9}$

Bons estudos!