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

14.06.2025 08:40

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^2 - 1

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What’s the worst thing you caught anyone in your family doing?

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

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Can a cop pull you over walking home asking why you are out so late?

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n^2 - n + n - 1

Why would a person always be so tired?

Move the nub up to the top:

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

(n - 1)(n + 1)

Does the Lil Wayne song ‘Lollipop’ refers to a Lollipop sweet or a metaphor?

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

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

The Roman Empire at the time of Christ kept meticulous records. Why then, is there no record of the trial of Jesus?

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