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Are the formulas that make up a disjunction called conjuncts? I am new to logic and need to know this for an assignment.

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  • $\begingroup$ Question is unclear, but you might be looking for either literals or clauses $\endgroup$ – angryavian Dec 15 '15 at 0:24
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    $\begingroup$ The question is very clear and the answer is no. Probably what the OP needs to know is that a disjunctive normal form is a disjunction of conjunctions. $\endgroup$ – Rob Arthan Dec 15 '15 at 0:37
  • $\begingroup$ If you can give us an assignment question using these words, it might make it clearer. However, typically @Rob Arthan is right. A disjunction is made up of disjuncts, just as a sum is made up of summands. But this language is not very common, and disjunct/conjunct is mostly used when referring to Normal Forms. $\endgroup$ – Alexander Heyes Dec 15 '15 at 1:11
  • $\begingroup$ They're (sometimes) called disjuncts. Similarly, the formulas that make up a conjunction are (sometimes) called conjuncts. $\endgroup$ – BrianO Dec 15 '15 at 2:12
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A disjunction is the logical "or" operation, $A\vee B$, also written as $A+B$ in boolean algebra.

A conjunction is the logical "and" operation, $A\wedge B$, a.w.a. $A\cdot B$.

The disjunctive normal form (DNF) is a disjunctive sequence of conjunctions.   For example: $(A{\wedge} B)\vee(C{\wedge}\neg A)\vee (\neg B{\wedge}\neg C)$ awa $A{\cdot}B+C{\cdot}\bar A+\bar B{\cdot}\bar C$ - a sum of products.

The conjunctive normal form (CNF) is a conjunctive sequence of disjunctions.   For example: $(\neg A{\vee} B{\vee} \neg C)\wedge(A{\vee}\neg B{\vee}C)$ a.w.a. $(\bar A{+}B{+}\bar C)\cdot(A{+}\bar B{+}C)$ - a product of sums.

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