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Math Help - Don't know how to solve this one

  1. #1
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    Don't know how to solve this one

    While working on some physics exercises today, I got stuck on an algebra problem. A simplified version would look something like this:

    x^2+x\sqrt(x^2-10)=5

    Anyone have a neat little trick for this type of problem?
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  2. #2
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    Quote Originally Posted by TwoPlusTwo View Post
    While working on some physics exercises today, I got stuck on an algebra problem. A simplified version would look something like this:

    x^2+x\sqrt(x^2-10)=5

    Anyone have a neat little trick for this type of problem?
    Write it as:

    x\sqrt(x^2-10)=5-x^2

    And then square both sides.
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  3. #3
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    Subtract [tex]x^2[tex] from both sides to give x\sqrt{x^2-10} = 5-x^2

    You can now square both sides but check for extraneous solutions by subbing back into your equation. Also note that x^2-10 \geq 0


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