$$ x^{\frac{1}{4}}.x^{\frac{1}{6}}=? $$

$$ x^{\frac{1}{4}}.x^{\frac{1}{6}}=x^{\frac{1}{4}+\frac{1}{6}} $$

$$ =x^{\frac{3+2}{12}} $$

$$ =x^{\frac{5}{12}} $$

$$ =(x^5)^{\frac{1}{12}} $$

$$ =\sqrt[12]{x^5} $$