Answer
I hope this helps if not im sorry :)
Step-by-step explanation:
Recall that the schema R of Exercise 7.1 is:
R(A,B,C,D,E)
with the functional dependencies:
A → BC
CD → E
E → A
To decompose R into 3NF, we first check if it is already in 3NF. Since there is only one candidate key (A), and all non-prime attributes (B, C, D, E) depend only on A, R is already in 3NF.
Therefore, the lossless, dependency-preserving decomposition into 3NF of R is simply:
R1(A, B, C)
R2(C, D, E)
where R1 includes the first functional dependency and R2 includes the second and third functional dependencies.