WEBVTT

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

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Simplify the polynomial expression in a, b.

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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. a squared: 1 minus 1 equals 0; ab: 2 plus 2 equals 4; b squared: 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 4ab.

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After expanding and combining like terms the expression is 4ab, a polynomial of degree 2 with 1 term.

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Spot check at a equals 0.73, b equals 1.14: original 3.3288, simplified 3.3288, which checks out.