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

12.06.2025 15:40

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

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

Why does it seem that Quora's "moderators" base their moderations on personal beliefs and views by deleting answers that are only violating their personal feelings?

n^2 - n + n - 1

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

Move the nub up to the top:

What are the strangest parts of The Bible?

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

(n - 1)(n + 1)

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Do you agree with Kamala Harris that Donald Trump is dangerous?

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n^2 - 1

"More problems than it was helping”: Behind the growing distrust of antidepressants - Salon.com

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

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