Question 1070274
Here are two odd numbers.
2n+1, and 2n-1, for some integer, n.


We believe that (2n+1)(2n-1) will be 'even', and we can simplify the product expression, through multiplication:
{{{2n*2n+2n-2n-1}}}
{{{4n^2-1}}}
But, is this 'even', or not?


The {{{4*n^2}}} is undoubtedly EVEN.  To that is subtracted the ODD number, 1, which together makes  4n^2-1, the product of the two odd numbers, an ODD number.