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| Use of Venn diagrams in Logic |
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| Venn diagrams are used very frequently on problems of “set theory”. Venn diagrams can also be used for deciding the truthfulness of statements. |
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| Example: |
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| 1) Represent the statement “some teachers are scholars” by using a venn diagram. |
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| Suggested answer: |
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| Let U be the universal set of all persons. |
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| Let T be the set of teachers and |
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| S be the set of scholars. |
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| Since “some teachers are scholars”, we have |
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| The truth of the given statement is depicted in the following venn diagrams. |
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| Case (i) |
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| Case (ii) |
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