In exponents we have this rule for division:
[tex] \frac{x^{a}}{x^{b}} = x^{a-b} [/tex]
Applying this rule for the given expression
[tex] \frac{x^{5}}{x^{8}} = x^{5-8} = x^{-3} [/tex]
Now we can use another rule here:
[tex] \frac{1}{x^{a}} =x^{-a} [/tex]
changing negative power to positive:
[tex] \frac{1}{x^{3}} =x^{-3} [/tex]
[tex] \frac{2x^{5}}{4x^{8}} = \frac{1}{2x^{3}} [/tex]
