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

Last Updated: 24.06.2025 11:09

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

n^2 - n + n - 1

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

xxxx

What happens when you need emergency surgery in countries with universal healthcare vs the US?

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

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

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

Common Psychiatric Medications May Increase Risk of ALS - ScienceAlert

Move the nub up to the top:

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

n^2 - 1

Why are the bands Smashmouth and Nickelback often used as punchlines?

xxxx

xx

xxx

Isn't it ironic people always talk about how much women hate Donald Trump, when almost any of them would marry him if they could? What he said in the 2005 Billy Bush video, almost every woman would share the sentiment if it got them his lifestyle.

xxx x

xxx

xxx x

Bank of Japan leaves interest rate unadjusted at 0.5% as expected - FXStreet

(n - 1)(n + 1)