Take away the parentheses



Rearrange the factors



Since  2•3 = 6, we have:



Those roots have the same index, so
we can multiply the numbers under
them an just have one cube root:



And since 4•16 = 64,



Maybe you already know that the cube root of 64 is 4, and
that you'd have 6•4 which is 24. But if you don't you can 
do this instead:

Break 64 down like this:
64 = 4•4•4 = 43, so we have:



When the index of the root and the exponent
of the radicand are the same, the cube root
cancels out the cube:



and all that's left is the number under the
radical:



And that's just



Edwin