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Math Help - The function f (x)

  1. #1
    Newbie Bluerabbits's Avatar
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    Exclamation The function f (x)

    Let f(x) = 1 - 2x^{2} and determine


    b) f(1-\sqrt{3})

    I know that Im supposed to put the above functions number 1 - squart 3 on the functions x place.

    This is how far Ive come:
    Im getting the number to
    f(1-\sqrt{3})= 1 - 2 (1-\sqrt{3})^{2}

    is this correct and if, what should I do now?
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  2. #2
    Super Member Quacky's Avatar
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    Re: The function f (x)

    Looks good so far. Expand and simplify.
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  3. #3
    Newbie Bluerabbits's Avatar
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    Re: The function f (x)

    Quote Originally Posted by Quacky View Post
    Looks good so far. Expand and simplify.
    \gg 1 - 2 (1-\sqrt{3}) (1-\sqrt{3})<br />

    Is this correct? Should I now eliminate \sqrt{3} now?
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  4. #4
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    e^(i*pi)'s Avatar
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    Re: The function f (x)

    Quote Originally Posted by Bluerabbits View Post
    \gg 1 - 2 (1-\sqrt{3}) (1-\sqrt{3})<br />

    Is this correct? Should I now eliminate \sqrt{3} now?
    You've not expanded, you've written the equation in the OP just in a different way.

    To expand (1-\sqrt3)^2 use FOIL (or whichever method you learned for expanding (a+b)^2)
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