Divide the polynomials using long division.

(81b^4-1)/(3b+1)

27b^3 - 27b^2 + 27b - 27

_________________________
3b + 1 | 81b^4 + 0b^3 + 0b^2 + 0b - 1
- (81b^4 + 27b^3)
_________________________
- 27b^3 + 0b^2 + 0b
+ 27b^3 + 9b^2
_________________________
- 9b^2 + 0b - 1
+ 9b^2 + 3b
_________________________
3b - 1

Therefore, the result of dividing (81b^4 - 1) by (3b + 1) using long division is:
27b^3 - 27b^2 + 27b - 27 with a remainder of 3b - 1.