WEBVTT

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Here is the problem: (x minus 1)(x plus 1).

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Simplify the polynomial expression in x.

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Read the expression.

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Distribute (multiply out every product). Each term in one factor multiplies each term in the other: a(b plus c) equals ab plus ac.

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Result after multiplying out.

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Combine like terms. x: 1 minus 1 equals 0. Like terms have identical variables and exponents, so only their coefficients are added.

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Write the result in standard form. Terms are ordered by descending total degree.

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So the answer is x squared minus 1.

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After expanding and combining like terms the expression is x squared minus 1, a polynomial of degree 2 with 2 terms.

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Spot check at x equals 0.73: original negative 0.4671, simplified negative 0.4671, which checks out.