Why is (n-1)(n+1)=n^2-1?

Last Updated: 16.06.2025 14:20

Why is (n-1)(n+1)=n^2-1?

The basic answer is that you cross-multiply the values in each factor:

xxx

So, that’s a rectangle with sides 2 and 4.

Brain cortex structure linked to mental abilities and psychiatric disorders - Medical Xpress

If you cut off the end of that rectangle, you make it smaller, 2 * 3 and a separate nub of size 1 * 2

n^2 - n + n - 1

Move the nub up to the top:

Why do I have the impression that almost all questions about advertising the flat Earth theory come from people who don't believe in a flat Earth themselves and are just provoking?

xxx x

And you are left with almost a square. One less than the square of side n.

xxx x

Beautiful European women were killed by inquisition but Russia was not Catholic. Is this the reason for a drastic difference explaining why Russian women are the prettiest?

xxx

xxxx

xx

What are the best ways to treat seasonal allergies?

The more direct answer is to look at a rectangle with sides of n + 1 and n - 1, let’s go with n = 2

(n - 1)(n + 1)

xxxx

What legal actions can be taken if a neighbor's unleashed dog causes harm or injury?

n^2 - 1