it means in multivalue dependency we don't care about functional dependency?

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the option b is correct . there is just a small definition of multivalue dependencies which . if a->> c is a dependency it means for a ,c has more than one value.

here it is saying whenever a appears b has same value which is true in case of functional dependency . if a->b exist for every a if repeats there should be same b . so a-.b exist here and it is clearly saying c is not same which means for same a it contains multipule value of c. so answer is b .

why not c ??

just consider the case

a is 1

and for c

A C

1 3

1 4

now u can see that for a we have multipule value of c but c does not have multiple values for a . so we cannot say c->>a . but we can say a->>c. and question is saying c can take different value not a .

here it is saying whenever a appears b has same value which is true in case of functional dependency . if a->b exist for every a if repeats there should be same b . so a-.b exist here and it is clearly saying c is not same which means for same a it contains multipule value of c. so answer is b .

why not c ??

just consider the case

a is 1

and for c

A C

1 3

1 4

now u can see that for a we have multipule value of c but c does not have multiple values for a . so we cannot say c->>a . but we can say a->>c. and question is saying c can take different value not a .

0

no basically the whole multi value functional dependency thing is lot more tricky. but reading it all and then just getting confussed is worthless. what i have taught is just a technique that is sufficient to answer every multivalue dependency question in gate. every function dependency is a multivalue dependency .

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