Question is not clear.
Case 1: (expression as posted)
using property of log : log(x)/k=log(x^(1/k), i.e. kth root
log(8) / 5 =log(8^(1/5))=log(2^(3/5)
Case 2: (expression with addition of parentheses around "8 over 5")
using property of log : log(x/y)=log(x)-log(y)
log(8/5)=log(8)-log(5)