Simplify square root of (4j^4)/(9k^8)

$\sqrt{\frac{4 j^{4}}{9 k^{8}}}$

Rewrite $4 j^{4}$ as ${(2 j^{2})}^{2}$ .

$\sqrt{\frac{{(2 j^{2})}^{2}}{9 k^{8}}}$

Rewrite $9 k^{8}$ as ${(3 k^{4})}^{2}$ .

$\sqrt{\frac{{(2 j^{2})}^{2}}{{(3 k^{4})}^{2}}}$

Rewrite $\frac{{(2 j^{2})}^{2}}{{(3 k^{4})}^{2}}$ as ${(\frac{2 j^{2}}{3 k^{4}})}^{2}$ .

$\sqrt{{(\frac{2 j^{2}}{3 k^{4}})}^{2}}$

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

$\frac{2 j^{2}}{3 k^{4}}$