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    I have a problem with this question ( image attached)

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    THe answer solution attached

    my problem is that for the f(x) function; f(x) = 4x -8 x< 5. therefore that range of x should be from the X-coordinate of A to x = 4 not 5. I thought that since it is x< 5, why did the author used x = 5.
    In summary looking at the worked solution; shouldn't the author use;
     \int_{2}^{4}(4x-8)dx
    instead using
     \int_{2}^{5}(4x-8)dx

    I am confused that is why I am asking for help. Pleae if someone to can explain to me.

    Thank you very much.


    This question is from madasmaths
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    (Original post by bigmansouf)
    I have a problem with this question ( image attached)


    THe answer solution attached

    my problem is that for the f(x) function; f(x) = 4x -8 x< 5. therefore that range of x should be from the X-coordinate of A to x = 4 not 5. I thought that since it is x< 5, why did the author used x = 5.
    In summary looking at the worked solution; shouldn't the author use;
     \int_{2}^{4}(4x-8)dx
    instead using
     \int_{2}^{5}(4x-8)dx

    I am confused that is why I am asking for help. Pleae if someone to can explain to me.

    Thank you very much.


    This question is from madasmaths
    But if you only went to x = 4 then that would miss out the area between x = 4 and x = 5.
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    (Original post by Notnek)
    But if you only went to x = 4 then that would miss out the area between x = 4 and x = 5.
    thank you
 
 
 
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