WEBVTT

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Here is the problem: (x to the power 4 minus 1)/(x squared plus 1).

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Simplify the rational expression in x: factor, cancel common factors and state excluded values.

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Write as a single fraction.

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Factor the numerator and denominator.

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Cancel the common factor. The factor x squared plus 1 appears in both the numerator and the denominator. Cancelling it does not change the value wherever the original expression is defined.

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State the excluded values. No real value makes a denominator zero.

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So the answer is (x minus 1)(x plus 1).

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In lowest terms the result is (x minus 1)(x plus 1) (expanded: x squared minus 1). Excluded values: none.

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The simplified form was compared with the original at four test points and agrees.