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

Last Updated: 20.06.2025 15:57

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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One day, I happened to walk past where my crush was with friends. Then all of a sudden they start laughing, and someone maybe him, goes "freaking (my name) with her freaking hair!" Can anyone offer insights into this? We're in middle school.

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

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(n - 1)(n + 1)

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

n^2 - n + n - 1

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Why did Mark Lane harass Helen Markham during an illegally recorded telephone conversation to misidentify Lee Harvey Oswald who she witnessed as the shooter of Tippit?

n^2 - 1

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.

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Move the nub up to the top: