Write square root b^5/ 4 square root b^3 as a single radical using the smallest possible root

√(b^5) / 4√(b^3)

= b^(5/2) / 4b^(3/2)

= (b^((5/2) - (3/2))) / 4

= b^(2/2) / 4

= b / 4√b