`B=3^1+3^2+...+3^7+3^8*(3^0+3^1+3^2+...+3^92) equiv 81 + (3^0 + 3^1+3^2+...+3^92) equiv 81+(3^0+3^1+...+3^7) + 3^8*(3^0+3^1+...+3^84) equiv 81+(3^0+3^1+...+3^7) + (3^0+3^1+...+3^84) equiv 81+2*(3^0+3^1+...+3^7)+3^8*(3^0+3^1+...+3^76) equiv ... equiv 81+11*(3^0+3^1+...+3^7)+3^8*(3^0+3^1+...+3^4) equiv 81+11*(3^0+3^1+...+3^7) + (3^0+...+3^4) equiv 81+11*3280+121 equiv 36282 equiv 38  (mod 82)`

Vậy `B` chia `82` dư `38`