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4.3: Radical Equations

  • Page ID
    203427
    • Roy Simpson, Cosumnes River College
    • OpenStax

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    Solving Radical Equations Containing One Radical

    Definition: Radical Equation

    An equation in which unknowns (variables) are part of a radicand is called a radical equation.

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    Caution: Solving Equations Containing Even-Indexed Radicals

    Care must be taken when working with expressions and equations involving even-indexed radicals. This is due to the nature of such beasts. Remember, the argument of an even-indexed radical cannot be negative, nor can an even-indexed radical return a negative value.

    Definition: Extraneous Solution

    An extraneous solution, also known as a spurious solution, is a root of a transformed (manipulated) equation that is not a root of the original equation because it was excluded from the domain of the original equation.

    Definition: Contradiction

    A contradiction is a statement that is both true and false simultaneously.

    Solving Equations Containing Rational Exponents

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    Solve this if the constant on the right side is very negative.

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    Solving Radical Equations with Two Radicals

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    How To: Solve a Radical Equation
    1. Isolate one of the radical terms on one side of the equation.
    2. Raise both sides of the equation to the power of the index.
    3. Are there any more radicals?
      If yes, repeat Step 1 and Step 2 again.
      If no, solve the new equation.
    4. Check the answer in the original equation.
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    This page titled 4.3: Radical Equations is shared under a CC BY 4.0 license and was authored, remixed, and/or curated by Roy Simpson, Cosumnes River College (OpenStax) via source content that was edited to the style and standards of the LibreTexts platform.