化简或计算.√9a²+27a⁴﹙a<0﹚

问题描述:

化简或计算.√9a²+27a⁴﹙a<0﹚

a原式=√[9a²(1+3a²)]
=√(9a²)√(1+3a²)
=|3a|√(1+3a²)
=-3a√(1+3a²)