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Math Help - function help

  1. #1
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    function help

    For the function g(x) = x2 + 5x - 2, determine g(-3x).
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  2. #2
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    g(x) = x^2 + 5x - 2

    g() = ()^2 + 5() - 2

    so ... what would g(-3x) be?
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  3. #3
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    Just sub -3x in for x and solve the equation.
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  4. #4
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    Quote Originally Posted by skeeter View Post
    g(x) = x^2 + 5x - 2

    g() = ()^2 + 5() - 2

    so ... what would g(-3x) be?
    What are in placement of those happy faces? -3?
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  5. #5
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    Quote Originally Posted by william View Post
    What are in placement of those happy faces? -3?
    Since the question asked g(-3x) (not g[-3]) you must sub in -3x not just -3 for the x's in the equation.
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  6. #6
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    Quote Originally Posted by skeeter View Post
    g(x) = x^2 + 5x - 2

    g() = ()^2 + 5() - 2

    so ... what would g(-3x) be?
    g(-3x)= (-3x)^2+5(-3x)-2=9x^2-15x-2, correct?
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  7. #7
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    g(-3x)= (-3x)^2 + 5(-3x) - 2 = 9x^2 - 15x - 2
    there you go ... it wasn't that difficult, was it?
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  8. #8
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    Quote Originally Posted by skeeter View Post
    there you go ... it wasn't that difficult, was it?
    quite simple
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