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Prove that \( 2^{4m}-1\) is divisible by 15,where \(m\) is any integer.

Note by Ravi Ranjan 2 years, 3 months ago

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2 \times 3

2^{34}

a_{i-1}

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2^4 = 1 (mod 15) or, 2^4m = 1 (mod 15) or, 2^4m -1 = 0 (mod 15)

And it's proved.

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Put m=1 2^4=16 16-1=15 15 is divisible on 15... Answer is yes......(2^4m)-1 is divisible on 15.....

You did not prove it, you just checked a case. Checking a case that does not represent all other cases is not a proof.

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Easy Math Editor

`*italics*`

or`_italics_`

italics`**bold**`

or`__bold__`

boldNote: you must add a full line of space before and after lists for them to show up correctlyparagraph 1

paragraph 2

`[example link](https://brilliant.org)`

`> This is a quote`

Remember to wrap math in \( ... \) or \[ ... \] to ensure proper formatting.`2 \times 3`

`2^{34}`

`a_{i-1}`

`\frac{2}{3}`

`\sqrt{2}`

`\sum_{i=1}^3`

`\sin \theta`

`\boxed{123}`

## Comments

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TopNewest2^4 = 1 (mod 15) or, 2^4m = 1 (mod 15) or, 2^4m -1 = 0 (mod 15)

And it's proved.

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Put m=1 2^4=16 16-1=15 15 is divisible on 15... Answer is yes......(2^4m)-1 is divisible on 15.....

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You did not prove it, you just checked a case. Checking a case that does not represent all other cases is not a proof.

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