Special elements of the set are the unity (its value is always 1) and the zero (its value is always 0).

Question

Special elements of the set are the unity (its value is always 1) and the zero (its value is always 0).

Answer

It must be proved since it is a theorem of the Boole-algebra.

Answer

Can not be proved since it is the  5th  postulate.

Answer

Can not be proved since it is the   6th  postulate.

Answer

It can be proved since it is consequence of the postulates.

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