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Prove that n2-1 divisible by 8 whenever n is an odd positive integer.

Short Answer

Expert verified

8 divides n2-1 whenever n is a positive integer

Step by step solution

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01

Step: 1

If n=0,

0 - 0 = 0

it is true for n=0.

02

Step: 2

Let P(k) be true.

k2-1

We need to prove that P(k+1) is true.

03

Step: 3

(k+2)21=k21+(4k+4)

It is divisible by 8.

It is true for P(k+1) is true.

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