1.5 Lösning 3c

\( {x^{-5} \cdot x^9 \over (x^{-9})^{1/3}} = {x^{-5+9} \over x^{-9 \cdot {1 \over 3}}} = {x^4 \over x^{-9 \over 3}} = {x^4 \over x^{-3}} = {x^{4-(-3)}} = x^{4+3} = x^7 \)