1.5 Lösning 3c
Från Mathonline
\( \displaystyle{ {x^{-5} \cdot x^9 \over (x^{-9})^{1/3}} \, = \, {x^{-5+9} \over x^{-9 \cdot {1 \over 3}}} \, = \, {x^4 \over x^{-9 \over 3}} \, = \, {x^4 \over x^{-3}} \, = \, {x^{4-(-3)}} \, = \, x^{4+3} \, = \, x^7 } \)