Why is (n-1)(n+1)=n^2-1?
Last Updated: 01.07.2025 06:06

xx
So, that’s a rectangle with sides 2 and 4.
n^2 - 1
UN calls for investigation into killings near Gaza aid site - BBC
Move the nub up to the top:
xxxx
xxx x
n^2 - n + n - 1
xxx
If you cut off the end of that rectangle, you make it smaller, 2 * 3 and a separate nub of size 1 * 2
First look at Battlefield 6 campaign leaks from latest test - Video Games Chronicle
The more direct answer is to look at a rectangle with sides of n + 1 and n - 1, let’s go with n = 2
And you are left with almost a square. One less than the square of side n.
(n - 1)(n + 1)
Trump’s FTC will approve an ad merger — with a gift to Elon Musk’s X - The Verge
xxx x
xxxx
The basic answer is that you cross-multiply the values in each factor:
Panama Canal boss warns MSC ports deal threatens principle of neutrality - ft.com
xxx