Practice Using Proof By Contradiction For Single Proposition (10.1.3.3.1)

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6 sample questions

Question 1.
What is proof by contradiction?
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Consider how assuming the opposite can reveal inconsistencies.
Question 2.
Give an example of proof by contradiction.
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Think about rational numbers that result from fractions.
3Question 3.
What does proof by contradiction involve?
- Assuming a statement is true
- Assuming a statement is false
- Directly proving the statement
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Reflect on the logical sequence of proving truths.
4Question 4.
True or False: Proof by contradiction can be used only for implications.
- True
- False
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Consider its application beyond just implications.
Question 5.
Prove that if the sum of two irrational numbers can be rational, provide an example.
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Look at properties of numbers and their sums.
Question 6.
Demonstrate that there exists no smallest positive rational number.
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Reflect on the structure of rationals and their properties.

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