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    How do I find the range of the function? I know the range is the value y takes, so should I sub x = 0 into the equation? How do I know which way the inequality arrows go?

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    look at the graph. where can y go and not go (look at the asymptote)

    if you have x tending to negative infinity what happens to y and if you have x tending to infinity what happens to y.
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    (Original post by w4rtorn)
    look at the graph. where can y go and not go (look at the asymptote)

    if you have x tending to negative infinity what happens to y and if you have x tending to infinity what happens to y.
    Sorry, I still don't understand.

    The range can't be less than the asymptote?

    Y crosses at 4?
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    (Original post by gottastudy)
    Sorry, I still don't understand.

    The range can't be less than the asymptote?

    Y crosses at 4?
    Y never crosses 4, hence the asymptote. basically y can't be lower than four because however small x is e^(2x) will always be positive and as x tends to negative infinity 2e^(2x) will tend to 0 and so 2e^(2x)+4 will tend to 4. that's why the graph looks the way it does. so whatever x is y will always be bigger than 4. y>4
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    (Original post by w4rtorn)
    Y never crosses 4, hence the asymptote. basically y can't be lower than four because however small x is e^(2x) will always be positive and as x tends to negative infinity 2e^(2x) will tend to 0 and so 2e^(2x)+4 will tend to 4. that's why the graph looks the way it does. so whatever x is y will always be bigger than 4. y>4
    I see...Thank you for the explanation.
 
 
 
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