MATH SOLVE

4 months ago

Q:
# Which of the following disjunctions is false ?A. 4 - 3 = 2 or 6 · 3 = 9B. 5 · 6 = 30 or 3 + 4 = 7C. 8 + 3 = 11 or 5 · 4 = 23D. 7 + 6 = 13 or 5 · 2 = 10

Accepted Solution

A:

A disjunction is false if both parts of the disjunction are false; otherwise, it is true

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Choice A

4-3=2 is false

6*3=9 is false

both parts are false, so overall the entire disjunction is false

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Choice B

5*6=30 is true

3+4=7 is true

Neither part is false, so overall the entire thing is true

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Choice C

8+3=11 is true

5*4=23 is false

While second piece is false, the overall disjunction is true. The first part (true) makes the whole thing true.

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Choice D

7+6=13 is true

5*2=10 is true

Neither part is false, so overall the entire thing is true

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In summary, we have

A. False

B. True

C. True

D. True

Making choice A the only answer that is false. So choice A is the final answer

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Choice A

4-3=2 is false

6*3=9 is false

both parts are false, so overall the entire disjunction is false

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Choice B

5*6=30 is true

3+4=7 is true

Neither part is false, so overall the entire thing is true

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Choice C

8+3=11 is true

5*4=23 is false

While second piece is false, the overall disjunction is true. The first part (true) makes the whole thing true.

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Choice D

7+6=13 is true

5*2=10 is true

Neither part is false, so overall the entire thing is true

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In summary, we have

A. False

B. True

C. True

D. True

Making choice A the only answer that is false. So choice A is the final answer