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Math Help - f * g * h

  1. #1
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    f * g * h

    Hello,

    Can you please verify that I did the correct operation?
    <br />
f(x) = 2x-1
    g(x) = x^2
    h(x) = 1 - x

    2(1-x)^2 -1
    2(1-x^2)-1
    2-2x^2-1
    -2x^2-1

    Thanks!
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  2. #2
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    Quote Originally Posted by l flipboi l View Post
    Hello,

    Can you please verify that I did the correct operation?
    <br />
f(x) = 2x-1
    g(x) = x^2
    h(x) = 1 - x

    2(1-x)^2 -1
    2(1-x^2)-1
    2-2x^2-1
    -2x^2-1

    Thanks!
    or should the answer be?
    2x^2-4x+1
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  3. #3
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    Dear l flipboi l,

    I think intead of {2(1-x^2)-1}\mbox{ it should be }{2(1-2x+x^2)-1}
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  4. #4
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    Quote Originally Posted by Sudharaka View Post
    Dear l flipboi l,

    I think intead of {2(1-x^2)-1}\mbox{ it should be }{2(1-2x+x^2)-1}
    Sudharaka,

    actually, you're right...you just expanded (1-x^2).
    Last edited by l flipboi l; January 8th 2010 at 05:52 PM. Reason: mistake
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  5. #5
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    f(g[h(x)])=2(g[h(x)])-1=2([h(x)]^2)-1

    =2(1-x)^2-1=2(1-2x+x^2)-1=2x^2-4x+1
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  6. #6
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    Dear l flipboi l,

    No I did'nt expand 2(1-x^2)-1,\mbox{ I expanded }{2(1-x)^2-1}
    Last edited by Sudharaka; January 8th 2010 at 08:28 PM.
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