XOR gate to XNOR gate boolean algebra

AI Thread Summary
The discussion focuses on converting an XOR gate with negated inputs and outputs into an XNOR gate using Boolean algebra. The initial formula presented was incorrect, leading to confusion about achieving the expected output. A suggestion was made to use a truth table to clarify the outputs for the four possible inputs. The correct approach involves inverting one input of the XOR gate, leading to the expression A' XOR B, which simplifies to A XNOR B. The final simplified expression is A'B' + AB, confirming the expected output of the XNOR gate.
Ogakor
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Xor gate with negated input and negated output.

The expected output is an XNOR gate. I can't get it with boolean algebra.

My initial formula is:
((AB')' + (A'B)')'

The expected output is:
AB + (AB)' right?

Please help me.
 
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Is this your homework?
 
thecritic said:
Is this your homework?

No, this was my seatwork and I didn't get the answer.
 
must you show it with boolean algebra? I'd recommend, since this has only 2 inputs and 1 output, simply running through the 4 possible inputs and calculating the 4 possible outputs 1 at a time in a truth table.
 
Ogakor said:
Xor gate with negated input and negated output.

The expected output is an XNOR gate. I can't get it with boolean algebra.

My initial formula is:
((AB')' + (A'B)')'

The expected output is:
AB + (AB)' right?

Please help me.
Neither of those expressions looks right to me.
 
I'm pretty sure that we're talking about inverting only one of the inputs to the XOR gate.
So, instead of A XOR B, we would have A' XOR B

This would, in fact have the result as A XNOR B
 
[(AB')+(A'B)]'

By De Morgan's Theorem
(AB')' • (A'B)'

Again by De Morgan's Theorem
(A'+B'') • (A''+B')

Simplify
(A'+B) • (A+B')

Multiply
A'A+A'B'+AB+BB'

*AA' and BB' are equal to 0

Therefore [(AB')+(A'B)]' = A'B'+AB
Hope this helps
 
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