Simplify square root of fourth root of x^6

$\sqrt{\sqrt[4]{x^{6}}}$

Factor out $x^{4}$ .

$\sqrt{\sqrt[4]{x^{4} x^{2}}}$

Pull terms out from under the radical.

$\sqrt{x \sqrt[4]{x^{2}}}$

Rewrite $\sqrt[4]{x^{2}}$ as $\sqrt{\sqrt{x^{2}}}$ .

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

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

$\sqrt{x \sqrt{x}}$