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    Name:  14835282760091516752987.jpg
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    (Original post by coconut64)
    Name:  14835282760091516752987.jpg
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Size:  314.3 KB are my ranges for g(x) right ? One of them doesn't match the answer thanks

    Attachment 608266608264
    The first range is right.
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    (Original post by solC)
    The first range is right.
    g(x)<-7 is unnecessary since -7<8 anyway
    So-7 is also right ? Thanks
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    (Original post by coconut64)
    So-7 is also right ? Thanks
    In fact, that second one is wrong because, even with the first range, g(x)<-7 doesn't make sense because there are clearly values between -7 and 8 as seen from the graph.
    Ignore what I first said, sorry.
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    (Original post by solC)
    In fact, that second one is wrong because, even with the first range, g(x)<-7 doesn't make sense because there are clearly values between -7 and 8 as seen from the graph.
    Ignore what I first said, sorry.
    The second equation -x^2+3 has a domain of x>3 , so surely the range has to be less than -7
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    (Original post by coconut64)
    are my ranges for g(x) right ? One of them doesn't match the answer thanks
    Both your answers are correct. What were the answers given?

    EDIT : Wrong, ignore.
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    (Original post by solC)
    In fact, that second one is wrong because, even with the first range, g(x)<-7 doesn't make sense because there are clearly values between -7 and 8 as seen from the graph.
    Ignore what I first said, sorry.
    Are you looking at the correct graph?

    You should be looking at the graph of y=-x^2+7 restricted to x&gt;3.

    Coconut64 has drawn it correctly.

    EDIT: Wrong, ignore.
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    (Original post by notnek)
    Are you looking at the correct graph?

    You should be looking at the graph of y=-x^2+7 restricted to x&gt;3.

    Coconut64 has drawn it correctly.

    The answer given was g(x)<=8, so I assumed that they treated the whole thing as a single function.
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    (Original post by coconut64)
    are my ranges for g(x) right ? One of them doesn't match the answer thanks
    I just noticed you posted the answers in your OP. Can you also post a picture of the actual question i,e, a photograph of the textbook?
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    (Original post by notnek)
    I just noticed you posted the answers in your OP. Can you also post a picture of the actual question i,e, a photograph of the textbook?
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    (Original post by coconut64)
    are my ranges for g(x) right ? One of them doesn't match the answer thanks
    Ignore what I've said so far. I just looked at your question again and noticed that g(x) is a single function. This is not two separate functions.

    Did you realise that?
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    (Original post by solC)
    The answer given was g(x)<=8, so I assumed that they treated the whole thing as a single function.
    It is a single function - I read the question incorrectly.

    So you're correct, sorry
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    (Original post by notnek)
    It is a single function - I read the question incorrectly.

    So you're correct, sorry
    So if the questions are laid out like this gx then 2 equations , there is only one function so only one range should be given? But there are 2 domains though...
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    (Original post by coconut64)
    So if the questions are laid out like this gx then 2 equations , there is only one function so only one range should be given? But there are 2 domains though...
    The function is equal to 3x-1 for x\leq 3 and equal to -x^2+7 for x&gt;3.

    So the domain of the function is actually all real numbers. It's just defined differently over different parts of the domain but it's a single function.

    The range of the function is the set of values that f can be over the full domain. So in your graph, it's anything that y can be.
 
 
 
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