Answer
$\sqrt[6]{(x-5)^5}$
Work Step by Step
RECALL:
For nonegative numbers a and b,
$\sqrt[n]{a} \cdot \sqrt[n]{b} = \sqrt[n]{ab}$
Also,
$(x-c)^{a}+(x-c)^{b}=(x-c)^{ab}$
Use the rules above to obtain:
$=\sqrt[6]{(x-5)(x-5)^4}
\\=\sqrt[6]{(x-5)^{1+4}}
\\=\sqrt[6]{(x-5)^5}$
