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The negation of the Boolean expression $$x \leftrightarrow \sim y$$ is equivalent to:
We have to find the negation (logical NOT) of the Boolean statement $$x \leftrightarrow \sim y$$ and then express the result in a simplified disjunctive form so that it can be matched with one of the given options.
First of all, let us recall the standard equivalence for a biconditional. The formula for any two propositions $$p$$ and $$q$$ is:
$$p \leftrightarrow q \;=\; (p \wedge q)\;\vee\;(\sim p \wedge \sim q).$$
Now we apply this rule to the concrete biconditional $$x \leftrightarrow \sim y$$ by replacing $$p$$ with $$x$$ and $$q$$ with $$\sim y$$. Doing so gives:
$$x \leftrightarrow \sim y \;=\; (x \wedge \sim y)\;\vee\;(\sim x \wedge \sim(\sim y)).$$
The double negation inside the second conjunct can be removed with the rule $$\sim(\sim y)=y$$. Hence we get:
$$x \leftrightarrow \sim y \;=\; (x \wedge \sim y)\;\vee\;(\sim x \wedge y).$$
We must now take the negation of the whole expression. So we write:
$$\sim\bigl(x \leftrightarrow \sim y\bigr) \;=\; \sim\Bigl[(x \wedge \sim y)\;\vee\;(\sim x \wedge y)\Bigr].$$
To push the negation inside the parentheses, we invoke De Morgan’s law, which states:
$$\sim(A \vee B)\;=\;(\sim A) \wedge (\sim B).$$
Here $$A$$ is $$x \wedge \sim y$$ and $$B$$ is $$\sim x \wedge y$$. Therefore:
$$\sim\Bigl[(x \wedge \sim y)\;\vee\;(\sim x \wedge y)\Bigr] \;=\; \bigl[\sim(x \wedge \sim y)\bigr] \;\wedge\; \bigl[\sim(\sim x \wedge y)\bigr].$$
The next step is to remove each inner negation. Again, we apply De Morgan’s law, this time in the form $$\sim(A \wedge B) = (\sim A) \vee (\sim B).$$ For the first bracket we have $$A = x$$ and $$B = \sim y$$:
$$\sim(x \wedge \sim y) \;=\; (\sim x) \;\vee\; (\sim(\sim y)) \;=\; (\sim x) \vee y.$$
For the second bracket we have $$A = \sim x$$ and $$B = y$$:
$$\sim(\sim x \wedge y) \;=\; (\sim(\sim x)) \;\vee\; (\sim y) \;=\; x \vee (\sim y).$$
So the entire expression is now
$$\bigl[(\sim x) \vee y\bigr] \;\wedge\; \bigl[x \vee (\sim y)\bigr].$$
To simplify, we distribute the conjunction across the disjunctions. The distributive law tells us:
$$(A \vee B)\wedge(C \vee D) \;=\; (A \wedge C)\;\vee\;(A \wedge D)\;\vee\;(B \wedge C)\;\vee\;(B \wedge D).$$
Letting $$A = \sim x,\; B = y,\; C = x,\; D = \sim y,$$ we compute each product term one by one:
1. $$(\sim x) \wedge x = \text{False},$$ because a proposition and its negation cannot both be true.
2. $$(\sim x) \wedge (\sim y) = \sim x \wedge \sim y.$$
3. $$y \wedge x = x \wedge y.$$
4. $$y \wedge (\sim y) = \text{False},$$ again because a variable and its negation cannot both be true.
Combining the surviving non-false terms under disjunction gives:
$$(\sim x \wedge \sim y)\;\vee\;(x \wedge y).$$
Conventionally we write the positive term first, so we obtain the final simplified negation as:
$$ (x \wedge y)\;\vee\;(\sim x \wedge \sim y). $$
Now we match this with the options provided. Option B is exactly
$$(x \wedge y) \vee (\sim x \wedge \sim y).$$
Hence, the correct answer is Option 2.
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