WEBVTT

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Here is the problem: (x plus 2) squared minus (x minus 2) squared.

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Simplify the polynomial expression in x.

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Read the expression.

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Expand powers of sums. Write (a plus b) to the power n as repeated multiplication and multiply out; e.g. (a plus b) squared equals a squared plus 2ab plus b squared.

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Result after multiplying out.

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Combine like terms. x squared: 1 minus 1 equals 0; x: 4 plus 4 equals 8; constants: 4 minus 4 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 8x.

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After expanding and combining like terms the expression is 8x, a polynomial of degree 1 with 1 term.

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Spot check at x equals 0.73: original 5.84, simplified 5.84, which checks out.