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# Question on integration watch

1. I have a problem with this question ( image 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;

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

Thank you very much.

Attached Images

2. (Original post by bigmansouf)
I have a problem with this question ( image 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;

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

Thank you very much.

But if you only went to x = 4 then that would miss out the area between x = 4 and x = 5.
3. (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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