SOLUTION: what is (x-y)n when n is odd

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Question 410576: what is (x-y)n when n is odd
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
any number exactly divisible by 2 is an even number (result is an integer).

any number that is not exactly divisible by 2 is an odd number (result is not an integer).

1 is odd
3 is odd
5 is odd

2 is even
4 is even
6 is even

if the number ends in 1,3,5,7,9, then the number is odd.

if the number ends in 0,2,4,6,8, then the number is even.

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an odd number times an odd number will always be an odd number.

example:

501 is odd (ends in 1)
733 is odd (ends in 3)

501 * 733 results in a number that ends in 3 which is odd (367233).

367233 / 2 = 183616.5 which is not an integer.

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an odd number times an even number will always be an even number.

example:

501 is odd (ends in 1)
730 is even (ends in 0).

501 * 730 results in a number that ends in 0 which is even (365730).

365730 / 2 = 182865 which is an integer.

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an even number times an odd number will always be an even number.

just take 501 * 730 and make it 730 * 501 and you get the same answer (even).

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an even number times an even number will always be an even number.

502 is even (ends in 2)
738 is even (ends in 8)

502 * 738 results in a number that ends in 6 which is even (370476).

370476 / 2 = 185238 which is an integer.

the rules are therefore:

odd * odd = odd
odd * even = even
even * odd = even
even * even = even

what this suggests is:

if n is odd, then (x-y) * n is even or odd depending on whether (x-y) is even or odd. you get odd * odd = odd, and you get even * odd = even.

if n is even, then (x-y) * n is always even regardless of whether (x-y) is even or odd. you get odd * even = even, and you get even * even = even.