- #1

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**Prime Division HELP!**

## Homework Statement

I need to be able to understand and likely prove that for any positive odd integer n,

8 | (n^2 -1 )

## Homework Equations

## The Attempt at a Solution

odd can be said to be n = 2k +1

so 8 | (2k + 1)^2 -1

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- #1

- 18

- 0

I need to be able to understand and likely prove that for any positive odd integer n,

8 | (n^2 -1 )

odd can be said to be n = 2k +1

so 8 | (2k + 1)^2 -1

- #2

Science Advisor

- 5,131

- 2,146

Keep going. Now expand out (2k+1)^2 - 1 and collect terms. Then think about the terms in k and k+1.

- #3

- 18

- 0

I got stumped trying mathematical induction i was hoping for a new approach

- #4

Mentor

- 37,229

- 9,391

Try the approach that phyzguy is suggesting.

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