1. The problem statement, all variables and given/known data Simplify the following xyz + x'(w+z') + yz(w+z') 2. Relevant equations 3. The attempt at a solution xyz + x'(w + z') + yz(w + z') xyz + x'w + x'z' + yz(w + z') xyz + x'w + x'z' + yzw + yzz' xyz + x'w + x'z' + yzw + 0 I got the answer xyz + x'w + x'z' + yzw However in the book it says the answer is xyz + x'w + x'z'. How could that be? I don't see any way of getting rid of yzw. Please tell me if this is correct or I need to fix something. Thank you.