(Boolean Algebra) Did I write this logic expression correctly?

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Discussion Overview

The discussion revolves around the correctness of a logic expression derived from Boolean algebra, with participants exploring methods for validation and simplification. The scope includes homework-related inquiries and technical reasoning regarding logical expressions and their representations.

Discussion Character

  • Homework-related
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant presents their logic expression Y=A+((A*B)+B+C'+(B+C'*D)+D) and seeks validation of its correctness.
  • Another participant suggests using intermediate expressions and parentheses for clarity, as well as applying Boolean algebra for simplification.
  • Several participants express that the initial presentation of the logic was messy and difficult to read, leading to corrections regarding the placement of parentheses and the need for negation in NAND gates.
  • A participant acknowledges a mistake in their expression and presents a revised version, F=A+(A*B)+(B*C')+(((B+C')*D)'+D)', asking for feedback on its correctness.
  • Another participant emphasizes the importance of a step-by-step approach to allow for review and validation of each part of the expression.
  • One participant concludes with a different final expression, C'+A+B, indicating a potential disagreement on the simplification outcome.

Areas of Agreement / Disagreement

There is no consensus on the correctness of the final expressions, as participants present differing views and results, indicating multiple competing interpretations of the logic expressions.

Contextual Notes

Participants express uncertainty about the correctness of their expressions and the methods used, highlighting the need for careful validation and the potential for errors in logical representation.

Who May Find This Useful

This discussion may be useful for students learning Boolean algebra, those seeking methods for validating logic expressions, and individuals interested in the step-by-step approach to problem-solving in logic design.

michalodzien
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Homework Statement


5c7c19e54a06b3c38414cbf3ad4e2750.png


My solution, is this correct?
This is what I came up with.
Y=A+((A*B)+B+C'+(B+C'*D)+D)
Is it safe to say that it is correct or did I make a mistake?
 

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I’d write the intermediate expressions at the gate output and put parentheses around them until you get to the final gate.

Also I’d use the bar over an expression to indicate negation.

Lastly. You can then apply Boolean algebra to reduce the long expression to get your final expression.

Try that and see if you can validate your own work. Doing it with intermediate results helps until you get good at it.
 
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jedishrfu said:
I’d write the intermediate expressions at the gate output and put parentheses around them until you get to the final gate.

Also I’d use the bar over an expression to indicate negation.

Lastly. You can then apply Boolean algebra to reduce the long expression to get your final expression.

Try that and see if you can validate your own work. Doing it with intermediate results helps until you get good at it.
487d6b7c22a98ebf0bf126817d93626b.png


I actually did these parts beforehand but i am not sure if what i came up with is correct and i would like to validate it before i start simplifying it.
Also i have no way to check if it correct because this is for an assignment which i will not get back with feedback but only with a grade.

If you would be so kind to help me on my mistakes and guide me to do this correctly, or just give me the answer i would appreciate it a lot. Either one is fine with me.
 

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Your paper is very messy and hard to read.

R = A + B
X = B + C'
Y = ( ( B + C' ) * D )'

Look at the Y gate again.
 
jedishrfu said:
Your paper is very messy and hard to read.

R = A + B
X = B + C'
Y = ( ( B + C' ) * D )'

Look at the Y gate again.
I am sorry for the paper quality.

I see i did a very silly mistake and forgot to add parentheses around B + C' and ofcourse It's a NAND gate so the expression needs a negation as a whole. I can see i did same mistake with E gate it should have been ((B+C'*D)'+D)'

This is the result i got now:

F=A+(A*B)+(B*C')+(((B+C')*D)'+D)'

It looks correct to me, does it so to you?
 
Students are always looking for the geodesic when the real geodesic is the step by step approach with intermediate values allowing someone to review it and check each step.

R = A * B (I made a mistake as it was an AND gate)
X = B + C'
Y = ( ( B + C' ) * D )'

E = ( Y + D )' = ( ( ( B + C' ) * D )' + D )'

G = R + X + E = (A * B) + (B + C') + ( ( ( B + C' ) * D )' + D )'

F = A + G = A + (A * B) + (B + C') + ( ( ( B + C' ) * D )' + D )'

Can you check my work?
 
jedishrfu said:
Students are always looking for the geodesic when the real geodesic is the step by step approach with intermediate values allowing someone to review it and check each step.

R = A * B (I made a mistake as it was an AND gate)
X = B + C'
Y = ( ( B + C' ) * D )'

E = ( Y + D )' = ( ( ( B + C' ) * D )' + D )'

G = R + X + E = (A * B) + (B + C') + ( ( ( B + C' ) * D )' + D )'

F = A + G = A + (A * B) + (B + C') + ( ( ( B + C' ) * D )' + D )'

Can you check my work?
It all looks correct and i can see this is an easy way to do it, thank you very much for your help!
 
Hmmm, I don't check this forum often so I'm a bit late to the party, but I get$$C'+A+B$$when it's all said and done.
 
Last edited:

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