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

10.06.2025 04:16

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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Why cant I add weight to my lifts even though im completing my sets? Every time I try to add more weight I cant even complete one rep.

(n - 1)(n + 1)

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n^2 - n + n - 1

If Russia needs the resources to fund the war in Ukraine, why doesn’t it throw open its doors to visa free western tourism? Enough people would be interested, & it would start to get some hard currency as €, CHF, £, SEK, $, JPY in the tills at shops.

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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

Move the nub up to the top:

What do you think of the controls that will be set up over information flows at Taiwan's Ministry of Foreign Affairs' missions?

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

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

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How often do you watch the news on TV?

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

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How can I fall asleep fast at night?

n^2 - 1