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R(ABCDE)
F = {AB->C, C->D, D->E, E->A}

AB+ = ABCDE
EB+ = ABCDE
DB+ = ABCDE
CB+ = ABCDE

CK ={ AB, CB, DB, EB} 

AB->C (no problem for BCNF)
C->D, D->E, E->A (3NF but not BCNF)

Decompose relation R as:
i. R1(ABC)  (CK: AB)  [BCNF]  {AB->C}

R2(ACDE)  (CK: C,D,E) [BCNF] {C->D, D->E, E->A}

C is CK for R2 and common attribute b/w R1 and R2.

Hence, this BCNF decomposition is losselss and Depedency Preserving!

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