suppose a relation R(ABCDE) and some FD are there like A->B, C->D
so to decompose it what i do is : suppose left side (A here not superkey {man lia) ) what i do is i will find A+ = AB
then from AB i leave A and I cancel B from R(ABCDE) giving me two table R1(AB) AND R2(ACDE)
but here https://gateoverflow.in/168294/bcnf-decomposition my method is failing if i follow same approach then i will get table BC not ABC