Question

помогите решите 3 и 5
пожалуйста

Answer 1

$\frac{1}{ {3}^{2} } - ( - \frac{1}{ {3}^{1} } ) = \frac{1}{9 } + \frac{1}{3} = \frac{1 + 3}{9} = \frac{4}{9}$
3*1/4^2+1/2^3=3*1/16+1/8=
=3/16+1/8=3+2/16=5/16