SOLUTION: explain how you know that 3^7+2 is an odd number 3^7 is 2187 add 2 is 2189 how do you prove? prove that the product of two odd numbers is always odd 7*7=49 how do you prove?

Question 1076912: explain how you know that 3^7+2 is an odd number
3^7 is 2187 add 2 is 2189 how do you prove?
prove that the product of two odd numbers is always odd
7*7=49 how do you prove?
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
prove that the product of two odd numbers is always odd
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Even numbers are 2m, 2n, etc
Odd numbers are 2m+1, 2n+1, etc
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For 2 odd numbers, 2n+1 and 2m+1,
(2n+1)*(2m+1) = 4mn + 2m + 2n + 1
4mn + 2m + 2n is even.
--> 4mn + 2m + 2n + 1 is odd.

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