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Math Help - Help on (f + g)

  1. #1
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    Help on (f + g)

    for both problems let: f (x)=x^2 + 4x and g(x)=x+2

    first problem:

    (f+g)(x) and (f+g)(3)


    second problem:

    (f-g)(x)and (f-g)(-1)
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  2. #2
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    earboth's Avatar
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    Quote Originally Posted by kbryant05
    for both problems let: f (x)=x^2 + 4x and g(x)=x+2

    first problem:
    (f+g)(x) and (f+g)(3)

    second problem:
    (f-g)(x)and (f-g)(-1)
    Hello,

    1rst problem: (f+g)(x)=x^2+4x+x+2 = x^2+5x+2

    To calculate (f+g)(x) plug in the value 3 for x:

    (f+g)(3)=3^2+5 \cdot 3+2 = 9+15+2=26

    2nd problem: (f-g)(x)=x^2+4x-(x+2) = x^2+3x-2

    To calculate (f-g)(-1) plug in the value (-1) for x:

    (f-g)(-1)= (-1)^2+3\cdot (-1)-2=1-3-2=-4

    Greetings

    EB
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  3. #3
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    Smile Thank You

    Thanks for explaining those two problems. It really helped me do the others that were similar!!
    Kristin
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