Final answer:
The expression (!x || y) || !(!x || y) evaluates to true in three different situations: when x and y are both true, when x and y are both false, and when x is true and y is false.
Step-by-step explanation:
To determine when the expression (!x || y) || !(!x || y) evaluates to true, we can consider the different cases:
- If both x and y have the initial value true, the expression will evaluate to true. This is because when x is true, the first part of the expression (!x || y) is false, but the second part !(!x || y) is true, therefore the whole expression is true.
- If both x and y have the initial value false, the expression will also evaluate to true. In this case, the first part of the expression (!x || y) will be true, and the second part !(!x || y) will also be true, resulting in the whole expression being true.
- If x has the value true and y has the value false, the expression will evaluate to true. Again, the first part of the expression (!x || y) will be true, and the second part !(!x || y) will also be true.
- In all other cases, the expression would not evaluate to true.