Question 1
Use proof by contradiction to determine which statement about the equation $x^2 + 5x + 3 = 0$ can be proven to be true.
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Specialist Mathematics · Unit 1 · Introduction to proof · The nature of proof
Use proof by contradiction.
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Question 2
A proof by contradiction is used to prove that quadrilateral ABCD is a parallelogram. Which of the following would be the correct assumption to start the proof?
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Question 3
Use proof by contradiction to show that if \(n^2\) is divisible by 5, then \(n\) is divisible by 5, where \(n\) is a positive integer.
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Question 4
Use proof by contradiction to show that if $n^2$ is an odd integer, then $n$ must be an odd integer.
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