A functional dependency is called a partial dependency if there is a proper subset

A functional dependency α → β is called a partial dependency if there is a proper subset γ of α such that γ → β.We says that β is partially dependent on α. A relation schema R is in second normal form (2NF) if each attributes A in R meets one of the following criteria:

• It appears in a candidate key.

• It is not partially dependent on a candidate key. Show that every 3NF schema is in 2NF.