WEBVTT

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Here is the problem: (a plus b) squared.

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Expand (a plus b) squared and collect like terms.

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

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So the answer is a squared plus 2ab plus b squared.

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After expanding and combining like terms the expression is a squared plus 2ab plus b squared, a polynomial of degree 2 with 3 terms.

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Spot check at a equals 0.73, b equals 1.14: original 3.4969, simplified 3.4969, which checks out.