9514 1404 393
Explanation:
The work can be done in your head, so there's really nothing to show.
If you want to go into painful detail, you can do this ...
[tex](2\sqrt{3x})(3\sqrt{6x^2})=(2\sqrt{3x})(3x\sqrt{6})=6x\sqrt{3\cdot6x}\\\\=6x\sqrt{3^2\cdot2x}=6x\cdot3\sqrt{2x}=\boxed{18x\sqrt{2x}}[/tex]
There may be some other intermediate steps you can show, or you can combine steps to the extent you think is appropriate.
