Logic Tool

In your assignments, logic questions will display with the Cengage Logic Tool. Use the Proof Builder within the tool to complete and check proofs.

1. Open an assignment that uses the Cengage Logic Tool.

2. Near the bottom of the assignment, click Proof Practice Tool under Supporting Materials.

3. Under Premise enter a line of your premise.

   If Premise comes pre-filled, move to the next step.

   1. Click to open and enter characters using the symbols pad.

      Common Logic Characters:

      Operator	Name	Logical Function	Used to translate
      ~	tilde	negation	not, it is not the case that
      ⋅	dot	conjunction	and, also, moreover
      ∨	wedge	disjunction	or, unless
      ⊃	horseshoe	implication	if... then..., only if
      ≡	triple bar	equivalence	if and only if

   2. If needed, click to add one or more premises.

4. Under Conclusion, click to enter a conclusion with the symbols pad.

   If Conclusion comes pre-filled, move to the next step.

5. Enter your proof.

   1. Click Enter a line of proof › to enter your proof.

   2. Click line # to enter numbers for your line of proof.

      Numbers must be entered in the format of a comma-separated list or a range of values.

      1,2 or 1-5.

      If line numbers are not needed to justify the proof, leave this box blank.

   3. Click Indent Line to indicate conditional or indirect proof sequences.

   4. Click Select a rule to enter a rule from the pad.

      Click under References to see a list of all the rules that can be input into your proof.

   5. Click to check if your line of proof is valid.

      If it's valid, a checkmark will show next to it. If invalid, a message titled Answer Feedback will appear and explain why.

   6. If needed, click to add additional lines of proof.

      Your previous line of proof must show as valid before you can add new lines.

   7. Click Delete line to delete a line of proof.

6. Click Check Proof to check the validity of the complete proof and re-check all lines of proof.