ShmoopTube

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And here is your shmoop math question de jour

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Multiply the quantity x minus 1 times the quantity x plus 1 times the quantity x minus 1

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And here are the potential answers...

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OK so what is this question asking?

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This one is really about how neat we are.

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No, not how super-terrific and all-over groovy we happen to be,

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but how tidy we are in terms of organizing our brute force methods of multiplying distributions.

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Start with just the quantity x minus 1 times the quantity x minus 1.

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Follow the arrows and we get x times x which is x squared

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x times 1 which is x

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... then negative 1 times x, which is negative x.

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then negative 1 times 1, which is 1.

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Now we just take the quantity x minus 1 and multiply it by the simplified x squared minus 1.

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We get x times x squared, which is x cubed and note that since we have a cubed here,

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we can eliminate 2 of the potential answers.

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Now we've got x squared times negative 1, which is negative x squared,

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then negative 1 times x which is negative x,

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and finally negative 1 times negative 1 which is positive 1.

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So the answer is right here: C.

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Neat-o.

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