# I Cant Understand Where Is My Error Here?

Discussion in 'Homework Help' started by transgalactic, Apr 29, 2008.

Apr 29, 2008
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2. ### Caveman Senior Member

Apr 15, 2008
471
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Your problem doesn't make sense. You simply didn't get the right answer because you interpreted it differently. In the actual solution only four cases output a zero:
[0001],[0011],[1001],[1011].

3. ### transgalactic Thread Starter Active Member

Apr 29, 2008
74
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ye i understand that we should take the minimal function from the karno table

i cant understand how did they build this mux using that function???

Apr 29, 2008
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5. ### Caveman Senior Member

Apr 15, 2008
471
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The mux gives the equation:
Y = !C*!D + B*C*D + !C*D*D + C*!D*D
The last term is always 0 because !D*D
The next to last term can drop the second D.
Then rearranging:
Y = !C*!D + !C*D + B*C*D
The first two terms can be combined.
Y = !C(!D + D) + B*C*D
The !D + D is always 1 so it can go away.
Y = !C + B*C*D
Since !C is covered, the C in the second term is redundant, so it can be removed.
Y = !C + B*D

6. ### Papabravo Expert

Feb 24, 2006
12,188
2,680
Because the world is not a fair and just place.

7. ### Caveman Senior Member

Apr 15, 2008
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Amen, brother.

8. ### transgalactic Thread Starter Active Member

Apr 29, 2008
74
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i understood the proccess when you took some expression
and transformed it into the minimal formula

i cant understand how did you got this big expression ???

i need some how to build a MUX from this minimal function that i got from tha table (i dont know how)
???

on the other hand i have here
a similar question which is solved by my way (circuling each row)

http://img166.imageshack.us/my.php?image=img8810ev2.jpg

is that a wrong way to solve it like that??