Please simplify this boolean algebra expression Simplify thi

Please simplify this boolean algebra expression:

Simplify this boolean algebra expression: r z (z + s + r)

Solution

The given Boolena expression is r\'z\'(z\'+s+r\')\'

= r\' z\'( z\'\' . s\' . r\'\') since according to demorgans theorem (A+B)\' = A\' . B\'

= r\' z\' ( z s\' r) since according to OR laws A\'\' = A

= r\' r z\' z s\'

= 0 since accoring to AND laws A.A\' = 0