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

Last Updated: 17.06.2025 06:21

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

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^2 - 1

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

How is it, in the USA, a country with 334 million people, the choice of President comes down to two aged men, one of whom is a liar as well as a criminal, one who appears to be on his way to dementia. Surely a democratic country can put up better?

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

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Move the nub up to the top:

I listened to Kamala Harris speech she gave in North Carolina. I support 100% of what she said. I am more and more in favor of a Kamala Harris presidency if Biden becomes unable to be our president! Do you find yourself supporting Kamala Harris now?

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(n - 1)(n + 1)

Why did Trump call Biden and Schumer Palestinians?

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

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

Can a cop pull you over walking home asking why you are out so late?

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n^2 - n + n - 1

Why do doctors refuse HRT to menopausal women but hand them out to trans people?

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