document.write( "Question 485685: Please help again, i have also posted this problem several times, and yet no response.
\n" ); document.write( "determine which if any of the three statements are equivalent. give a reason for your conclusion, and show complete work.
\n" ); document.write( "i)if the dog wags its tail, then the dog is not calm.
\n" ); document.write( "ii)either the dog does not wag its tail or the dog is not calm
\n" ); document.write( "iii) if the dog is not calm, then the dog wags its tail.\r
\n" ); document.write( "\n" ); document.write( "thank you for your help.
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Algebra.Com's Answer #332157 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
i)if the dog wags its tail, then the dog is not calm.
\n" ); document.write( "ii)either the dog does not wag its tail or the dog is not calm
\n" ); document.write( "iii) if the dog is not calm, then the dog wags its tail.\r
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\n" ); document.write( "\n" ); document.write( "p = the dog wags its tail.
\n" ); document.write( "q = the dog is not calm.\r
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\n" ); document.write( "\n" ); document.write( "~p = the dog does not wag its tail.
\n" ); document.write( "~q = the dog is calm.\r
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\n" ); document.write( "\n" ); document.write( "statement 1 translates to p -> q
\n" ); document.write( "statement 2 translates to ~p v q
\n" ); document.write( "statement 3 translates to q -> p\r
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\n" ); document.write( "\n" ); document.write( "statement 1 and 3 are not equivalent
\n" ); document.write( "we need to test with statement 2 to see if it's equivalent to either one of the other 2.\r
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\n" ); document.write( "\n" ); document.write( "when in doubt, you need to do a truth table.
\n" ); document.write( "it tells you whether the statement are equivalent or not.\r
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\n" ); document.write( "\n" ); document.write( "the truth table for these 3 statements is shown in the following picture.\r
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\n" ); document.write( "\n" ); document.write( "in this table:\r
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\n" ); document.write( "\n" ); document.write( "statement 1 becomes statement A.
\n" ); document.write( "statement 2 becomes statement B.
\n" ); document.write( "statement 3 becomes statement C.\r
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\n" ); document.write( "\n" ); document.write( "\"$$$$$\"/\r
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\n" ); document.write( "\n" ); document.write( "The truth table says that (p -> q) is equivalent to (~q v p).\r
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\n" ); document.write( "\n" ); document.write( "That means that statement 1 is equivalent to statement 2.\r
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\n" ); document.write( "\n" ); document.write( "It would be difficult to see this without use of the truth table.\r
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\n" ); document.write( "\n" ); document.write( "Logically, trying to make sense of it takes a little stretch.\r
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\n" ); document.write( "\n" ); document.write( "I believe the answer lies in the law of disjunction.\r
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\n" ); document.write( "\n" ); document.write( "The law of disjunction states:\r
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\n" ); document.write( "\n" ); document.write( "if A or B is true, then:
\n" ); document.write( "If A is false, then B must be true.
\n" ); document.write( "If B is false, than A must be true.\r
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\n" ); document.write( "\n" ); document.write( "we have 2 statements that we think are equivalent because the truth table test of equivalency says that they are.\r
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\n" ); document.write( "\n" ); document.write( "The 2 statements are:\r
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\n" ); document.write( "\n" ); document.write( "i)if the dog wags its tail, then the dog is not calm.
\n" ); document.write( "ii)either the dog does not wag its tail or the dog is not calm\r
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\n" ); document.write( "\n" ); document.write( "the contra-positive of the first statement and the first statement are equivalent.\r
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\n" ); document.write( "\n" ); document.write( "The first statement is:
\n" ); document.write( "if the dog wags its tail, then the dog is not calm.
\n" ); document.write( "The contra-positive to the first statement is:
\n" ); document.write( "if the dog is calm, then the dog does not wag its tail.\r
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\n" ); document.write( "\n" ); document.write( "The second statement is:
\n" ); document.write( "either the dog does not wag its tail or the dog is not calm.\r
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\n" ); document.write( "\n" ); document.write( "If we assume that the dog does not wag its tail is false, then the law of disjunction says that the dog is not calm must be true.\r
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\n" ); document.write( "\n" ); document.write( "we can write this another way to say:
\n" ); document.write( "if the dog wags its tail, then the dog is not calm.
\n" ); document.write( "that looks very much like the first statement.\r
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\n" ); document.write( "\n" ); document.write( "if we assume that the dog is not calm is false, then the dog does not wag its tail must be true by the same law of disjunction.\r
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\n" ); document.write( "\n" ); document.write( "we can write this another way to say:
\n" ); document.write( "if the dog is calm, then the dog does not wag its tail.
\n" ); document.write( "that looks very much like the contra-positive to the first statement.\r
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\n" ); document.write( "\n" ); document.write( "i'm satisfied that the truth table is telling the truth and that statements 1 and 2 are equivalent even though anybody would be hard pressed to determine that they are without using the rules of logic to confirm that.\r
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\n" ); document.write( "\n" ); document.write( "the truth table test is the way to determine the equivalency of two statements.\r
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\n" ); document.write( "\n" ); document.write( "that's called demorgan's law i believe.\r
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\n" ); document.write( "\n" ); document.write( "here's some additional reading for you if i didn't send it to you earlier.
\n" ); document.write( "there are references in there as well so you can study to your heart's content if you so desire.\r
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\n" ); document.write( "\n" ); document.write( "STATEMENT LAWS AND FALLACIES\r
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