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C3 graph with a constant Watch

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Size:  282.1 KB can anyone help with part c please? I am not sure if a is positive or negative so do I just assume a is 0? Thanks Attachment 584256584258
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    expand it first

    you should be able to solve for the intersection and roots once you do so
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    (Original post by coconut64)
    can anyone help with part c please? I am not sure if a is positive or negative so do I just assume a is 0? Thanks
    You can't assume it's zero.

    In this case "a" cannot be negative, otherwise you'll be raising a negative number to a real power - what's (-1)^{0.4} - which can't be sketched in a standard graph as it involves complex numbers.

    Note that if a >1, the exponential will be increasing.
    If a < 1 then it's decreasing.
    And if a=1 ?

    Can you take it from there.
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    (Original post by anonmouse221)
    expand it first

    you should be able to solve for the intersection and roots once you do so
    wHAT DO i EXPAND?
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    (Original post by ghostwalker)
    You can't assume it's zero.

    In this case "a" cannot be negative, otherwise you'll be raising a negative number to a real power - what's (-1)^{0.4} - which can't be sketched in a standard graph as it involves complex numbers.

    Note that if a >1, the exponential will be increasing.
    If a < 1 then it's decreasing.
    And if a=1 ?

    Can you take it from there.
    if a is 1 then I will get 1/x +1 and 1+1 for a^x+a...
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    (Original post by coconut64)
    if a is 1 then I will get 1/x +1 and 1+1 for a^x+a...
    Confusing. How can you get two different expressions when you set a=1, into part c?

    However, if a=1, then part c reduces to 1+1, and so, f(x)=2, i.e. constant.
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    (Original post by ghostwalker)
    Confusing. How can you get two different expressions when you set a=1, into part c?

    However, if a=1, then part c reduces to 1+1, and so, f(x)=2, i.e. constant.
    I am slightly lost too. There are 3 parts in part c and each part requires you to draw a graph. I don't get what you mean by f(x)=2 , so it is just a straight line?? Thanks
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    (Original post by coconut64)
    I am slightly lost too. There are 3 parts in part c and each part requires you to draw a graph. I don't get what you mean by f(x)=2 , so it is just a straight line?? Thanks
    Sorry, I thought you were just looking at the last part of part C, which is also called (c).

    This is a slightly unfair question, IMO, as the shape of the graph depends on the value of "a", If a >1, then its increasing, if a < 1 it's decreasing, and if a=1, it's a constant - i.e. just a straight line at y=2.
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    (Original post by ghostwalker)
    Sorry, I thought you were just looking at the last part of part C, which is also called (c).

    This is a slightly unfair question, IMO, as the shape of the graph depends on the value of "a", If a >1, then its increasing, if a < 1 it's decreasing, and if a=1, it's a constant - i.e. just a straight line at y=2.
    Sorry about the confusion! So what do I set a as ? It says a is just an arbitrary constant....
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    (Original post by coconut64)
    Sorry about the confusion! So what do I set a as ? It says a is just an arbitrary constant....
    It's arbitrary so, you can't set it as anything. I'd suggest drawing three graphs, one for each of the different scenarios.
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    (Original post by ghostwalker)
    It's arbitrary so, you can't set it as anything. I'd suggest drawing three graphs, one for each of the different scenarios.
    thanks
 
 
 
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