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Math Help - Finding the Limit

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    Finding the Limit

    can someone explain to me how sqrt(x^2 + x^4) became sqrt(1+x^2)?
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    Re: Finding the Limit

    Quote Originally Posted by l flipboi l View Post
    can someone explain to me how sqrt(x^2 + x^4) became sqrt(1+x^2)?
    You can factor out an x^2 from the expression under the square root: \sqrt{x^2(1+x^2)} and, by the laws of surds, \sqrt{x^2}\sqrt{1+x^2} = |x|\sqrt{1+x^2}

    The |x| which is now outside the radical is cancelled with the x in the numerator. (They have said that \sqrt{x^2} = x before cancelling which is OK if x>0[/tex]
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