Step 1: \ \

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The statement is \"\" is divisible by \"\". \ \

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Condition I:

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First show that, the above statement is true, when \"\".

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\"\" \ \

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\"\" \ \

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

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The statement is true for \"\".

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Condition I of the Principle of Mathematical Induction holds. \ \

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Step 2:

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Condition II :

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Assume that \"\"  is divisible by \"\".holds for some \"\", and determine whether the formula then holds for \"\". \ \

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Assume that, \"\" is divisible by \"\" for some \"\" -----> equation (1). \ \

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Now need show that, \"\" is divisible by \"\". \ \

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\"\" \"\" \ \

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\"\" \ \

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\"\" is divisible by \"\" and \"\" is divisible by \"\". \ \

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Therefore, \"\" is divisible by \"\". \ \

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Thus, Condition II also holds.

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The statement is true for all natural numbers. \ \

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Solution:

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The statement is true for all natural numbers. \ \