Wondering why the following boolean expression seem to have 2 possible simplification? Are these two both correct ? Thank you very much !
How online tutorial solves it:
How I simplify it
When you use a Karnaugh map you will see that they are the same. See the following Karnaugh map for this boolean expression, almost completely matched with circles:
The blue circle matches the expression BC
, the red circle matches the expression B'C'
. The remaining cell at AB'C
still needs a circle. There are three ways to create a circle, which matches this cell:
In this solution, the cell AB'C
is matched by a circle with only one cell. However this is not the biggest circle possible in this Karnaugh map. The circles chosen in a Karnaugh map are picked to be the biggest circle possible (according to the Karnaugh map rules).
The "real" other solutions are:
The green circle in this solution matches AC
. The remaining third solution is this one:
The green circle in this solution matches AB'
.
This means that all these three boolean expressions are equal:
BC + B'C' + AB'C
(can still be more simplified, shows what happens when too small circles are choose in Karnaugh maps)BC + B'C' + AC
(your solution)BC + B'C' + AB'
(solution from the video)