WEBVTT

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Here is the problem: x squared plus 1 greater than 0.

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Solve the inequality and give the answer in interval notation.

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Move everything to one side and factor. A sign chart needs the form f(x) compared with 0, written as a product/quotient of factors.

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Find the critical points. There are no real critical points, so the expression keeps one sign for every x.

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Write the solution set.

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So the answer is All real numbers: (-∞, ∞).

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The inequality holds exactly for x in All real numbers: (-∞, ∞). Points where the expression is undefined are never included, and endpoints are included only for less than or equal to or greater than or equal to where the expression equals zero.

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x equals 0: satisfies the inequality.