radical symbol[144x^10y^12z^18]
I need to simplify this. Can anyone help?

that does^ mean?

Exponent 2 power to the second

I'm not exacally sure cause you got more then on varible in there but for starts try factoring a 2 out of it and go from there.

Realise that:
\sqrt{144x^{10}y^{12}z^{18}} = \sqrt{144}\sqrt{x^{10}}\sqrt{y^{12}}\sqrt{z^{18}}

It should be easy from here.