मराठी

Prove the statement by using the Principle of Mathematical Induction: 32n – 1 is divisible by 8, for all natural numbers n.

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प्रश्न

Prove the statement by using the Principle of Mathematical Induction:

32n – 1 is divisible by 8, for all natural numbers n.

बेरीज
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उत्तर

P(n) = 32n – 1 is divisible by 8.

So, substituting different values for n, we get,

P(0) = 30 – 1 = 0 which is divisible by 8.

P(1) = 32 – 1 = 8 which is divisible by 8.

P(2) = 34 – 1 = 80 which is divisible by 8.

P(3) = 36 – 1 = 728 which is divisible by 8.

Let P(k) = 32k – 1 be divisible by 8.

So, we get,

⇒ 32k – 1 = 8x

Now, we also get that,

⇒ P(k + 1) = `3^(2("k" + 1))` – 1

= 32(8x + 1) – 1

= 72x + 8 is divisible by 8.

⇒ P(k + 1) is true when P(k) is true.

Therefore, by Mathematical Induction, P(n) = 32n – 1 is divisible by 8, for all natural numbers n.

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पाठ 4: Principle of Mathematical Induction - Exercise [पृष्ठ ७०]

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एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 11
पाठ 4 Principle of Mathematical Induction
Exercise | Q 6 | पृष्ठ ७०

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