मराठी

Prove the Following by Using the Principle of Mathematical Induction for All N ∈ N: `1 + 3 + 3^2 + ... + 3^(N – 1) =((3^N -1))/2

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प्रश्न

Prove the following by using the principle of mathematical induction for all n ∈ N

`1 + 3 + 3^2 + ... + 3^(n – 1) =((3^n -1))/2`

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उत्तर

Let the given statement be P(n), i.e.,

= `(3^(k+1) - 1)/2`

Thus, P(k + 1) is true whenever P(k) is true.

Hence, by the principle of mathematical induction, statement P(n) is true for all natural numbers i.e., n.

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