Engineering What is the output for the following logic circuit?

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The discussion centers on the output of a logic circuit, where participants analyze a provided solution that appears incorrect. The main point of contention is the role of variable C in the output, with consensus that C' should be included in the correct answer. Participants also question the alignment of the circuit diagram with the explanation, noting discrepancies in gate types. A Verilog module is shared, demonstrating the correct output as A' + B + C'. The conclusion is that the original solution in the study guide is likely a mistake, prompting the user to flag it for correction.
icesalmon
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Homework Statement
What is the output for the following logic circuit?
Relevant Equations
DeMorgan's Law
Logical Operations involving Logic Gates
I obtained the following result:
([(A xor B) xor 0]* AC)'
([(A'B + AB') xor (0)]*AC)'
[([A'B + AB']*(0)' + 0)*AC)]'
[(A'B + AB')*(1)*(AC)]'
[A'ABC + AB'AC]'
[AB'C]'
A'+B+C'
the solution to this problem is getting a different answer, I don't know why this solution isn't inverting the output AB'C
 

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I agree with your answer. I think the simplest way to see that the given answer is wrong is to consider how C appears in it. The only appearance of C is as an input to the final NAND. It seems that +C' must be in the correct answer.
 
FactChecker said:
I think the simplest way to see that the given answer is wrong

I was looking back and forth and at the given answer and wondering if the circuit and the explanation actually even go together. The explanation says the second gate is a NOR and the last gate is an AND but that's not what's drawn.

Code:
module problem2;
wire A,B,C,out;
reg [2:0] x;
assign out = !( A & C & (0^(A^B)) );
assign {A,B,C}=x[2:0];
initial begin
  $display("A B C | O");
  x=0;
  do begin
    #1 $display("%b %b %b | %b",A,B,C,out);
    x=x+1;
  end while(x!=0);
end
endmodule

Which yields A'+B+C'

Code:
A B C | O
0 0 0 | 1
0 0 1 | 1
0 1 0 | 1
0 1 1 | 1
1 0 0 | 1
1 0 1 | 0
1 1 0 | 1
1 1 1 | 1
 
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the errata for a study guide I'm using to prepare for the Fundamentals of Engineering Exam didn't include this correction and was issued in 2017 so I decided to ask here. The solution I included corresponded to the problem I posted in the study guide, I'm not sure what happened with the solution to this problem when it was written. But I'm convinced this is a mistake. Thanks for the help in verifying that it was a mistake, i'll just flag the problem and move on.
 
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Thread 'Why wasn’t gravity included in the potential energy for this problem?'
I’m looking at the attached vibration problem. The solution in the manual includes the spring potential energy but does NOT include the gravitational potential energy of the hanging mass. Can someone explain why gravitational potential energy is not included when deriving the equation of motion? I tried asking ChatGPT but kept going in circles and couldn't figure out. Thanks!

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