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## Homework Statement

Hi, I am trying to write the sum and output of a full adder in terms of XOR logical functions using boolean logic and Karnaugh maps. I've got the expressions from the Karnaugh maps fine but I can't seem to rearrange them into the expected form shown at the end of my working.

## Homework Equations

Explained above.

## The Attempt at a Solution

It's going to be difficult writing my working here but hopfully it is clear:

My equation obtained from the Karnaugh map using a minimized SOP:

Sum = NOT(A).NOT(B).C + NOT(A).B.NOT(C) + A.B.C + A.NOT(B).NOT(C)

Sum = NOT(A).(NOT(B).C + B.NOT(C)) + A.(B.C + NOT(B).NOT(C))

Sum = NOT(A).(B XOR C) + A.(B.C + NOT(B).NOT(C))

..

...

...

Sum = NOT(NOT(A).B + A.NOT(B)).C + (NOT(A).B + A.NOT(B)).NOT(C)

Sum = (A XOR B) XOR C

This is where I'm trying to get. I've tried going both backwards and forwards but I just don't know where to go in-between. Any suggests to get me past the 3rd step I'm at?

Thank you,

Dan