$\"\"$

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(a)

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The statement : $\"\"$ is divisible by $\"\"$ for all positive integers of $\"\"$

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Consider $\"\"$ and $\"\"$ .

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$\"\"$ .

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Substitute $\"\"$ .

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$\"\"$ it is not divisible by $\"\"$ .

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$\"\"$ is divisible by $\"\"$ is false.

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$\"\"$

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(b)

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Let the statement be $\"\"$ .

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Substitute $\"\"$ .

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$\"\"$ is divisible by $\"\"$ .

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$\"\"$ is true for $\"\"$ .

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Substitute $\"\"$ in $\"\"$ .

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$\"\"$

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$\"\"$ not divisible by $\"\"$ .

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Hence the conjecture is false.

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$\"\"$

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(a) $\"\"$ is divisible by $\"\"$ is false.

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(b) The conjecture is false for $\"\"$ .