Factoring #54a^9#
#color(white)("XXXX")##54a^9 = (9*6)(a^8*a)#
#color(white)("XXXX")##color(white)("XXXX")##=(3^2*6)((a^4)^2*a)#
#color(white)("XXXX")##color(white)("XXXX")##=(3a^4)^2*(6a)#
#sqrt(54a^9)#
#color(white)("XXXX")##=sqrt((3a^4)^2*(6a))#
#color(white)("XXXX")##=sqrt((3a^4)^2) *sqrt(6a#
#color(white)("XXXX")##=3a^4*sqrt(6a)#