Why is (n-1)(n+1)=n^2-1?
11.06.2025 23:59
The basic answer is that you cross-multiply the values in each factor:
Move the nub up to the top:
xxx x
And you are left with almost a square. One less than the square of side n.
If you cut off the end of that rectangle, you make it smaller, 2 * 3 and a separate nub of size 1 * 2
xxxx
The more direct answer is to look at a rectangle with sides of n + 1 and n - 1, let’s go with n = 2
xxx
(n - 1)(n + 1)
The Best Father's Day Gift Ideas for Every Type of Dad - IGN
n^2 - 1
So, that’s a rectangle with sides 2 and 4.
xxxx
xx
xxx
xxx x
Do Republicans give permission to Democrats to vote for any candidate except for Kamala Harris?
n^2 - n + n - 1