# Digital Electronics - Boolean Algebra and Logic Simplification - Discussion

Discussion Forum : Boolean Algebra and Logic Simplification - General Questions (Q.No. 45)

45.

The commutative law of addition and multiplication indicates that:

Discussion:

2 comments Page 1 of 1.
Nimuel said:
4 years ago

Answer A is associative law.

Variables are grouped in any way using parentheses. The key here is that the answer implies a possibility of more than two variables.

Say you have A + B + C. You can OR A and B first, then C later.

(A + B) + C

Alternatively, you can pair B and C first before pairing the result with A.

A + ( B + C)

Answer C is possible. Notice that it only talks about two variables. It also states that there is no difference in the output whether you OR variable A to B or you OR variable B to A.

So, we can say associative is about grouping variables. Commutative is about swapping variables.

Variables are grouped in any way using parentheses. The key here is that the answer implies a possibility of more than two variables.

Say you have A + B + C. You can OR A and B first, then C later.

(A + B) + C

Alternatively, you can pair B and C first before pairing the result with A.

A + ( B + C)

Answer C is possible. Notice that it only talks about two variables. It also states that there is no difference in the output whether you OR variable A to B or you OR variable B to A.

So, we can say associative is about grouping variables. Commutative is about swapping variables.

Sean said:
8 years ago

Isn't 'A' equivalent to 'C'?

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