若a＞0,化简根号-12a²b³=?

若a＞0,化简根号-12a²b³=?
若a＞0,化简根号-12a²b³=?

若a＞0,化简根号-12a²b³=?
a>0
而-12a²b³≥0
所以b≤0
|b|=-b
所以原式=根号[(4a²b²)(-3b)]
=|2ab|根号(-3b)
=-2ab根号(-3b)