Can you please provide the workings to show how we derive 12rt2?

Thanks

First, combine the 12 and 3 to see what we get --
It gives us 36. This is a perfect square.

Now, we have sqrt(36*8)
since sqrt(ab) = sqrt(a) * sqrt(b) we can separate our problem into
sqrt(36) * sqrt(8)
6 * sqrt(8)
Now, do the same with sqrt(8)
sqrt(8) = sqrt(4*2) = sqrt(4)*sqrt(2) = 2*sqrt(2)
Now, our whole problem is 6 * 2 * sqrt2 or 12*sqrt(2)

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