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

Last Updated: 16.06.2025 22:40

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

(n - 1)(n + 1)

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Is it ok to be spanked by your parents if you are not in bed in your set bedtime?

Move the nub up to the top:

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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Is it wrong of me to feel uncomfortable that my friend thinks my brother is hot?

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

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How can one justify in Sweden that total subsidies for public green energy initiatives being approximately 8.2 billion SEK per year? Electric cars at market price typically cost an average of 500,000 SEK which is above household budgets.

n^2 - 1

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

Why are Democrats deflecting and aren’t as tough on Hunter Biden with all of his criminal activity and his rising possibility of him receiving a charge for illegally owing a gun?

n^2 - n + n - 1

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

Why are right-wing commentators spreading conspiracy theories about Haitians eating local pets in Springfield, Ohio?

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