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Let the operations $$*, \odot \in \{\wedge, \vee\}$$. If $$(p * q) \odot (p \odot \sim q)$$ is a tautology, then the ordered pair $$(*, \odot)$$ is
We need to find the ordered pair $$(*, \odot)$$ from $$\{\wedge, \vee\}$$ such that $$(p * q) \odot (p \odot \sim q)$$ is a tautology.
Step 1: Test each option systematically.
Option B: $$(*, \odot) = (\vee, \vee)$$
The expression becomes: $$(p \vee q) \vee (p \vee \sim q)$$
$$= p \vee q \vee p \vee \sim q$$
$$= p \vee (q \vee \sim q)$$
$$= p \vee T$$
$$= T$$
This is a tautology.
Step 2: Verify that other options are not tautologies.
Option A: $$(*, \odot) = (\vee, \wedge)$$
$$(p \vee q) \wedge (p \wedge \sim q)$$
When $$p = F, q = T$$: $$(F \vee T) \wedge (F \wedge F) = T \wedge F = F$$. Not a tautology.
Option C: $$(*, \odot) = (\wedge, \wedge)$$
$$(p \wedge q) \wedge (p \wedge \sim q)$$
$$= p \wedge (q \wedge \sim q) = p \wedge F = F$$. Not a tautology (always false).
Option D: $$(*, \odot) = (\wedge, \vee)$$
$$(p \wedge q) \vee (p \vee \sim q)$$
When $$p = F, q = T$$: $$(F \wedge T) \vee (F \vee F) = F \vee F = F$$. Not a tautology.
Only Option B gives a tautology.
The correct answer is Option B: $$(\vee, \vee)$$
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