Answer :
[tex]\sqrt{\cfrac{3x^4}{5x}}\implies \sqrt{\cfrac{3x^3}{5}}\implies \sqrt{\cfrac{3x^{2+1}}{5}}\implies \sqrt{\cfrac{3x^2 x^1}{5}}\implies \sqrt{\cfrac{3x^2 x}{5}}\implies x\sqrt{\cfrac{3x}{5}}[/tex]
[tex]\sqrt{\cfrac{3x^4}{5x}}\implies \sqrt{\cfrac{3x^3}{5}}\implies \sqrt{\cfrac{3x^{2+1}}{5}}\implies \sqrt{\cfrac{3x^2 x^1}{5}}\implies \sqrt{\cfrac{3x^2 x}{5}}\implies x\sqrt{\cfrac{3x}{5}}[/tex]