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

16.06.2025 11:23

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

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

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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How is it not psychopathic to use someone for sex, even if they agree?

n^2 - n + n - 1

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How did your marriage end?

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

Why do I sweat a great deal while exercising the same on some days and not so much on others?

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

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How do you handle your mother-in-law after you heard her talking badly about you in the next room?

n^2 - 1

Move the nub up to the top:

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

What is your craziest/worst Halloween story?

(n - 1)(n + 1)