La seconda come richiesto:
(((- 5^6)/(-5)^4 + (-5)·(- 2^2) - 5^0)/((-3)^4/(-3)^3))^3·(48/(-2)^4)=
=((- 5^2 + 20 - 1)/(-3))^3·3=
=((-25 + 20 - 1)/(-3))^3·3=
=((-6)/(-3))^3·3= 2^3·3 = 8·3 = 24
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La seconda espressione:
$\small \left\{\left[(-5^6) : (-5)^4+(-5)(-2^2)-5^0\right] : \left[(-3)^4 : (-3)^3\right]\right\}^3·\left[48 : (-2)^4\right]=$
$\small =\left\{\left[-(5)^{6-4} +(-5)(-4)-1\right] : \left[(-3)^{4-3} \right]\right\}^3·\left[48 : 16 \right]=$
$\small =\left\{\left[-(5)^2 +20-1\right] : \left[(-3)^1 \right]\right\}^3·3=$
$\small =\left\{\left[-25 +20-1\right] : -3 \right\}^3·3=$
$\small =\left\{-6 : -3 \right\}^3·3=$
$\small =\left\{2 \right\}^3·3=$
$\small =8·3=$
$\small =24$