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    Hey! Right so I've already emailed my teacher, looked around on MyMaths/textbooks etc and so far, no good answers, so I have two questions:

    1. How do I find the range of a function?
    Simple, I know, but I'm just really struggling with how to do it.

    2. What on Earth am I doing with rates of change when t is infinity??

    Thanks in advance guys
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    (Original post by sadiowitch)
    Hey! Right so I've already emailed my teacher, looked around on MyMaths/textbooks etc and so far, no good answers, so I have two questions:

    1. How do I find the range of a function?
    Simple, I know, but I'm just really struggling with how to do it.

    2. What on Earth am I doing with rates of change when t is infinity??

    Thanks in advance guys
    1) Use the domain (possible x values) to consider the values of the function ie the 'y' values - a sketch might help.

    2) Can you give an example? Usually you have something like e^-t which tends to zero.
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    (Original post by Muttley79)
    1) Use the domain (possible x values) to consider the values of the function ie the 'y' values - a sketch might help.

    2) Can you give an example? Usually you have something like e^-t which tends to zero.
    This is the part I don't understand!

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    (Original post by sadiowitch)
    This is the part I don't understand!

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    As I said the term e to the power of -t tends to zero.
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    (Original post by Muttley79)
    As I said the term e to the power of -t tends to zero.
    Ah sorry, just realised why what I said doesn't make sense! It's because this is the answer for a), I don't understand how you get from this to the equation for m in c)!
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    (Original post by sadiowitch)
    Ah sorry, just realised why what I said doesn't make sense! It's because this is the answer for a), I don't understand how you get from this to the equation for m in c)!
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    As t gets large e^t gets large so we have a big number divided by a big number + 1 (which makes little difference to a big number). So effectively the numerator and denominator are the 'same' ie the fraction is 1.

    It's like 1000/1001 then 10 000/10 001 then etc
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    (Original post by Muttley79)
    As t gets large e^t gets large so we have a big number divided by a big number + 1 (which makes little difference to a big number). So effectively the numerator and denominator are the 'same' ie the fraction is 1.

    It's like 1000/1001 then 10 000/10 001 then etc
    Ooooooooh okay, thank you so much
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    (Original post by sadiowitch)
    Ooooooooh okay, thank you so much
    You are welcome
 
 
 
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