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

16.06.2025 05:56

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

(n - 1)(n + 1)

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Why do Brits drive a lot more dangerously compared to Americans? Is there just no courtesy when driving in the UK?

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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^2 - n + n - 1

Are there legal obligations to report the known whereabouts of a missing person that doesn’t want to be found?

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

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What is the scariest thing that ever happened in your life?

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

Move the nub up to the top:

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Do you think that drug addiction is a symptom of larger societal ills? What is it about our culture that leaves so many feeling like they're inadequate, trying any ill to find a cure?

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

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

California schools are very liberal. Do you think California schools are teaching students to hate Republican views (views on: God, guns, prayer, secure borders, etc.)?

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