Answer
$b^{17}$
Work Step by Step
RECALL:
(i) $(a^m)^n = a^{mn}$
(ii) $(ab)^m=a^mb^m$
(ii) $a^m \cdot a^n =a^{m+n}$
(iv) $a^0=1, a\ne0$
Use rule (i) above to obtain:
$=b^{5\cdot3}b^2
\\=b^{15}b^2$
Use rule (iii) above to obtain:
$=b^{15+2}
\\=b^{17}$
