Simplify square root of 4^3x^2

$\sqrt{4^{3} x^{2}}$

Raise $4$ to the power of $3$ .

$\sqrt{64 x^{2}}$

Rewrite $64 x^{2}$ as ${(8 x)}^{2}$ .

$\sqrt{{(8 x)}^{2}}$

Pull terms out from under the radical, assuming positive real numbers.

$8 x$