解：?$(1)\sqrt [3]{0.008}=\sqrt [3]{0.2^3}=0.2，$??$\sqrt [3]8=\sqrt [3]{2^3}=2，$??$\sqrt [3]{8000}=\sqrt [3]{20^3}=20$?
規(guī)律：被開方數(shù)的小數(shù)點(diǎn)向右?$($?左?$)$?移動(dòng)?$3$?位，其立方根的
小數(shù)點(diǎn)向右?$($?左?$)$?移動(dòng)?$1$?位
真命題：若?$\sqrt [3]{m}=n，$?則?$\sqrt [3]{1000\ \mathrm {m}}=10n$?
?$ (2)$?因?yàn)?$\sqrt [3]{0.001728}=0.12，$??$\sqrt [3]{a}=1.2，$??$1.2 = 0.12×10，$?
?$ $?所以?$a = 0.001728×1000 = 1.728$?
