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    I don't understand why 3^x graph has a range of y>0 why isn't it y greater than equal to 0
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    (Original post by Jane122)
    I don't understand why 3^x graph has a range of y>0 why isn't it y greater than equal to 0
    For what value of x do you think 3^x = 0 ?
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    (Original post by notnek)
    For what value of x do you think 3^x = 0 ?
    idk..
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    There is no value of x that makes y = 0
    If y = 3^x, When:
    x= 1, y = 3
    x= 0, y= 1
    x= -1 y = 1/3
    x= -2, y = 1/9

    This goes on forever, but will never reach y = 0 - only getting closer and closer to 0 but never actually reaching it.
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    y approaches 0 as x tends to negative infinity, but doesn't equal 0.
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    (Original post by JLegion)
    There is no value of x that makes y = 0
    If y = 3^x, When:
    x= 1, y = 3
    x= 0, y= 1
    x= -1 y = 1/3
    x= -2, y = 1/9

    This goes on forever, but will never reach y = 0 - only getting closer and closer to 0 but never actually reaching it.
    Is it because of the asymptote thing
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    Think about it this way.

    If y=3^x, since y>0 it means that whatever real number you choose x to be, y>0.
    Try with x=-1 ; y=3^(-1) = 1/3 > 0
    Try with x= 0 ; y=3^0 = 1
    Try with x=infinity ; y=3^(infinity) = infinity
    Try with x=-infinity ; y=3^(-infty) = 1/infty = 0

    Strictly though, we should use limits when talking about infinity but the above expanation works.

    In other words, for all real values of x, y will always be greater than zero.
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    (Original post by Jane122)
    Is it because of the asymptote thing
    There is an asymptote at y = 0. y gets closer and closer to y = 0 but never actually touches it.
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    (Original post by JLegion)
    There is an asymptote at y = 0. y gets closer and closer to y = 0 but never actually touches it.
    Ok so it's cause of the asymptote
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    (Original post by Jane122)
    I don't understand why 3^x graph has a range of y>0 why isn't it y greater than equal to 0
    The range is defined as all the values the function outputs.

    An asymptote is the vertical or horizontal line a function gets extremely close to, but never crosses it.

    In this case,  y = 0 would be the line the function gets infinitely close to!

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    (Original post by Naruke)
    The range is defined as all the values the function outputs.

    An asymptote is the vertical or horizontal line a function gets extremely close to, but never crosses it.

    In this case,  y = 0 would be the line the function gets infinitely close to!

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    Are Solomon worksheets good
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    (Original post by Jane122)
    Are Solomon worksheets good
    Yeah, but work on them once you've competed the textbook questions.

    Good luck fam
 
 
 
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