These are square roots, yes?
Here's how we type square roots: sqrt(x).
4 sqrt(3) * 2 sqrt(6)
We can rearrange this, using The Commutative Property of Multiplication
4 * 2 * sqrt(3) * sqrt(6)
You know what 4 times 2 is.
8 * sqrt(3) * sqrt(6)
There is a property for multiplying square roots.
sqrt(x) * sqrt(y) = sqrt(xy)
In other words, we multiply the radicands together.
8 * sqrt(3*6)
8 * sqrt(18)
Now we simplify the radical sqrt(18) by looking for squared factors of 18.
18 is 3^2 times 2
8 * sqrt(9*2)
Using the property above, this is the same as 8 * sqrt(9) * sqrt(2)
8 * 3 * sqrt(2)
24 sqrt(2) is the simplified product.