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What's the range of this function?

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    The function is f(x) = (2e^3x ) -1

    I think the range is any real number, am I right?
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    (Original post by Blake Jones)
    The function is f(x) = (2e^3x ) -1

    I think the range is any real number, am I right?
    No. What's the range for e^x? What about e^{3x}? They're the same. Now what about 2e^{3x}? Translate this answer down by 1 and you got it.

    Range is certainly never ALL real values with an e^x graph.
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    (Original post by Blake Jones)
    The function is f(x) = (2e^3x ) -1

    I think the range is any real number, am I right?
    Solve f(x)=-1
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    (Original post by Blake Jones)
    The function is f(x) = (2e^3x ) -1

    I think the range is any real number, am I right?
    consider e^x and the transformations needed to get to f(x), knowing that there is an asymptote at the x axis on the curve y=e^x .
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    (Original post by RDKGames)
    No. What's the range for e^x? What about e^{3x}? They're the same. Now what about 2e^{3x}? Translate this answer down by 1 and you got it.

    Range is certainly never ALL real values with an e^x graph.
    e^x has a range of all positive numbers right?
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    (Original post by Blake Jones)
    e^x has a range of all positive numbers right?
    No, exp(x)>0.
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    (Original post by Blake Jones)
    e^x has a range of all positive numbers right?
    If so, solve e^x=0 for me.
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    (Original post by B_9710)
    No, exp(x)>0.
    (Original post by RDKGames)
    If so, solve e^x=0 for me.
    Positive numbers don't include 0, which is why the term "non-negative" exists. So yes, he is right.
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    (Original post by Zacken)
    Positive numbers don't include 0, which is why the term "non-negative" exists. So yes, he is right.
    Yay! haha! So the 2 in the original question adjusts the range because if e^x had a smallest value of 1 (just for example) then the smallest range value when multiplied by 2 would be 2 right?
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    (Original post by Blake Jones)
    Yay! haha! So the 2 in the original question adjusts the range because if e^x had a smallest value of 1 (just for example) then the smallest range value when multiplied by 2 would be 2 right?
    sort of right, sort of not
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    (Original post by Blake Jones)
    Yay! haha! So the 2 in the original question adjusts the range because if e^x had a smallest value of 1 (just for example) then the smallest range value when multiplied by 2 would be 2 right?
    Indeed!
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    (Original post by MathMoFarah)
    sort of right, sort of not
    Hmm, okay, how should I approach this?

    I'm getting confused haha!
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    (Original post by Zacken)
    Indeed!
    And then the -1 moves it down by one so the range is any number bigger than -1?
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    (Original post by RDKGames)
    If so, solve e^x=0 for me.
    how do I write equations like that?
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    (Original post by Blake Jones)
    And then the -1 moves it down by one so the range is any number bigger than -1?
    Correct.
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    (Original post by KnowledgeIsBest)
    how do I write equations like that?
    Latex.

    http://www.thestudentroom.co.uk/wiki/LaTex
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    (Original post by Zacken)
    Correct.
    Thank you!
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    (Original post by Zacken)
    Positive numbers don't include 0, which is why the term "non-negative" exists. So yes, he is right.
    Didn't notice the word positive in there.
 
 
 
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