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I know XNOR is AB + A'B' so I thought the equation somehow expands to ax+bx+cx+a'x'+b'x'+c'x', but that doesn't seem right because (a+b+c)' is not the same as (a'+b'+c').

Karan Bijani
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    Welcome to EE.SE! This appears to be a homework question. As such, you need to show us your work so far, and explain which part of the question you're having trouble with. For future reference: Homework questions on EE.SE enjoy/suffer a special treatment. We don't provide complete answers, we only provide hints or Socratic questions, and only when you have demonstrated sufficient effort of your own. Otherwise, we would be doing you a disservice, and getting swamped by homework questions at the same time. See also here. – Dave Tweed Oct 02 '18 at 16:49
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    In this case, I didn't really know what to show because I have the equation but don't know how to get the next step. I do like that you don't give complete answers, that's good because I want to do it myself. – Karan Bijani Oct 02 '18 at 16:54
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    'that doesn't seem right because (a+b+c)' is not the same as (a'+b'+c')' -- Why are you focused on this case? – mike65535 Oct 02 '18 at 17:02
  • That's just what I thought it was, I realize now I was wrong (and how easy the real answer is). – Karan Bijani Oct 02 '18 at 17:03

1 Answers1

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If you introduce a temporary variable:

y = a + b + c

then you can rewrite the original expression as

yx + y'x'

Does this provide enough of a hint?

Dave Tweed
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  • Oh man, that's such an obvious solution. It's 1:00 am and I've been doing this for hours, which is why I missed something so obvious. Well, at least this is the last question. Thanks! – Karan Bijani Oct 02 '18 at 16:54